assignment for computer language

Browse Course Material

Course info, instructors.

• Prof. Eric Grimson
• Prof. John Guttag

Departments

• Electrical Engineering and Computer Science

As Taught In

• Programming Languages

Introduction to Computer Science and Programming

Assignments.

You are leaving MIT OpenCourseWare

Programming in Java   ·   Computer Science   ·   An Interdisciplinary Approach

Online content. , introduction to programming in java., computer science., for teachers:, for students:.

How to Learn Programming – The Guide I Wish I Had When I Started Learning to Code

Just the thought of learning to code can be very intimidating. The word code is mysterious by definition. It implies a technical form of communication that computers, and not humans, are meant to understand.

One way many people start learning to code is by picking a popular programming language and jumping in head first with no direction. This could take the form of an online coding course, a tutorial project, or a random book purchase on a specific topic.

Rarely do prospective developers start with a roadmap – a bird's eye view of the coding world that outlines a set of relevant programming concepts, languages, and tools that almost 100% of developers use every day.

In this article, I propose one such roadmap. I do this by outlining 14 steps – each one discussing an essential concept, language, or tool – that professional developers use to write code, collaborate, and create professional projects.

I meticulously chose these 14 steps based on my own personal journey learning to code, which spans almost 20 years.

Part of the reason it took me so long to feel comfortable as a developer is that I would learn about specific topics without a broader context of the coding world.

Each of the steps in this article discusses a "coding essential" – something that I believe is critical to at least know that it exists at the start of your coding journey.

One final note before listing the steps in the roadmap: of course reading this article will not make you an expert programmer. It isn't meant to. The purpose of this article is to make you aware that each one of these topics exists, and hopefully give you a basic idea of how each one works so you can build on it intelligently going forward.

14 Step Roadmap for Beginner Developers

• Familiarize Yourself with Computer Architecture and Data Basics
• Learn How Programming Languages Work
• Understand How the Internet Works
• Practice Some Command-Line Basics
• Build Up Your Text Editor Skills with Vim
• Take-up Some HTML
• Tackle Some CSS
• Start Programming with JavaScript
• Continue Programming with Python
• Further Your Knowledge with Java
• Track Your Code using Git
• Store Data Using Databases and SQL
• Read About Web Frameworks and MVC
• Play with Package Managers

Without further ado, let's start at the top!

1) Familiarize Yourself with Computer Architecture and Data Basics

One of the wonderful things about modern programming languages is that they enable us to create fancy applications without worrying about the nitty-gritty details of the hardware behind the scenes (for the most part).

This is called abstraction – the ability to work with higher-level tools (in this case programming languages) that simplify and narrow down the required scope of our understanding and skills.

However, that doesn't mean it's useless to know the basics of the metal that your code is executing on. At the very least, being aware of a few tidbits will help you navigate workplace conversations about high CPU and memory usage.

So, here is a bare minimum of computer architecture basics to get you started:

Your computer's most important parts live on microchips (also known as integrated circuits ).

Microchips rely on an electrical component called a transistor to function. Transistors are tiny electrical switches that are either off (0) or on (1) at any given time. A single microchip can contain millions or billions of tiny transistors embedded on it.

Most modern computers have a microchip called the Central Processing Unit (CPU) . You can think of it as the computer’s brain. It handles most of the number crunching and logical tasks that the computer performs.

Each CPU has something called an instruction set , which is a collection of binary (zeros and ones) commands that the CPU understands. Luckily, we don't really need to worry about these as software devs! That is the power of abstraction.

If the CPU is the logical center of the brain, it is useful to have memory as well to store information temporarily or for the long term.

Computers have Random Access Memory (RAM) as "working memory" (or short-term memory) to store information that is actively being used by running programs.

RAM is made up of a collection of memory addresses , which can be used to store bits of data. In older languages like C, programmers do have access to working directly with memory addresses using a feature called pointers , but this is rare in more modern languages.

Finally, we'll touch on a component you're surely familiar with – the hard drive. In our analogy of the brain, this represents long-term memory. A hard drive is an internal or external device that stores data that should persist even after the computer is turned off.

Before moving on to more details about programming languages, let's spend a second talking about data. But what exactly do we mean by the word data ?

At a high level, we think of things like text documents, images, videos, emails, files, and folders. These are all high-level data structures that we create and save on our computers every day.

But underneath the hood, a computer chip (like a CPU or RAM chip) has no idea what an "image" or a "video" is.

From a chip’s perspective, all of these structures are stored as long sequences of ones and zeros. These ones and zeros are called bits .

Bits are commonly stored in a set of eight at a time, known as a byte . A byte is simply a sequence of eight bits, such as 00000001 , 01100110 , or 00001111 . Representing information in this way is called a binary representation .

2) Learn How Programming Languages Work

In the previous section, we mentioned that most computers rely on a CPU, and a CPU can understand a specific set of instructions in the form of ones and zeros.

Therefore, we could theoretically write code that tells the CPU what to do by stringing together long sequences of ones and zeros in a form the CPU understands. Instructions written in binary form like this are called machine code .

Sounds horrible to work with, doesn't it? Well it probably is, but I wouldn't know since I mostly use higher-level programming languages like JavaScript, Python, and Java.

A higher-level programming language provides a set of human-readable keywords, statements, and syntax rules that are much simpler for people to learn, debug, and work with.

Programming languages provide a means of bridging the gap between the way our human brains understand the world and the way computer brains (CPUs) understand the world.

Ultimately, the code that we write needs to be translated into the binary instructions (machine code) that the CPU understands.

Depending on the language you choose, we say that your code is either compiled or interpreted into machine code capable of being executed by your CPU. Most programming languages include a program called a compiler or an interpreter which performs this translation step.

Just to give a few examples – JavaScript and Python are interpreted languages while Java is a compiled language. Whether a language is compiled or interpreted (or some combination of the two) has implications for developer convenience, error handling, performance, and other areas, but we won't get into those details here.

3) Understand How the Internet Works

Whatever type of programming you aspire to do, you'll run into situations where it helps to know how computers interact with each other. This typically occurs over the Internet.

The Internet is nothing more than a global collection of connected computers. In other words, it is a global network. Each computer in the network agrees on a set of rules that enable them to talk to each other. To a computer, "talking" means transferring data.

As we discussed in the previous section, all types of data – web pages, images, videos, emails, and so on – can all be represented as ones and zeros.

Therefore, you can think of the Internet as a very large set of computers that can transfer ones and zeros amongst themselves, in a way that preserves the meaning of that data. The Internet is nothing more than a digital conversation medium.

If the Internet is just a big conversation arena, let’s define the conversation participants.

First, an analogy: most human conversations require at least two participants. In most cases, one person initiates the conversation and the other person responds, assuming they are both present and available.

In Internet speak, the computer initiating the conversation is called the client . The computer responding or answering is called the server .

For example, let’s say you open a web browser and go to "www.google.com". In this scenario, your web browser is the client. By extension, you can also think of the computer you are working on as the client.

In a more abstract sense, YOU are the client because you are the one initiating the conversation. By typing "www.google.com" into the search bar and clicking <ENTER>, your browser is requesting to start a conversation with one of Google’s computers.

Google’s computer is called the server. It responds by sending the data required to display Google’s web page in your browser. And voilà! Google’s web page appears in front of your eyes. All Internet data transfers utilize this sort of client/server relationship.

4) Practice Some Command-Line Basics

The Command Line can be intimidating at first glance. It is often featured in movies as a cryptic black screen with incomprehensible text, numbers, and symbols scrolling by. It is usually associated with an evil hacker or genius techie sidekick.

The truth is that it doesn’t take a genius to use or understand the command line. In fact, it allows us to perform many of the same tasks that we are comfortable doing via a point-and-click mouse.

The main difference is that it primarily accepts input via the keyboard, which can speed up inputs significantly once you get the hang of it.

You can use the Command Line to browse through folders, list a folder’s contents, create new folders, copy and move files, delete files, execute programs, and much more. The window in which you can type commands on the Command Line is called a terminal .

Let's walk through a short tutorial of basic navigation commands that will give you a feel for working on the command line.

Once you open your terminal, a typical first question is " Where am I"? We can use the pwd command (which stands for "Print Working Directory") to figure that out. It outputs our current location in the file system which tells us which folder we are currently in.

Try it yourself:

How to Use the Command Line

If you’re on a Mac, open the Terminal app, which is essentially a Unix Command Line terminal.

If you’re running an operating system without a GUI (Graphical User Interface), like Linux or Unix, you should be at the Command Line by default when you start the computer. If your flavor of Linux or Unix does have a GUI, you’ll need to open the terminal manually.

At the prompt, type pwd and press <ENTER>. The Command Line will print out the path to the folder that you’re currently in.

By default, the active folder when opening the Command Line is the logged-in user’s home directory. This is customizable in case you want the convenience of starting in a different location.

For convenience, the home directory can be referenced using the tilde ~ character. We will use this in a few examples going forward.

Now that we know what folder we’re in, we can use the ls command to list the contents of the current directory. The ls command stands for "List".

Type ls and press <ENTER>. The contents (files and subfolders) that reside in the current directory are printed to the screen.

Rerun the previous command like this ls -al and press <ENTER>. Now we will get more details about the directory contents, including file sizes, modification dates, and file permissions.

The hyphen in the previous command allows us to set certain flags that modify the behavior of the command. In this case we added the -a flag which will list all directory contents (including hidden files) as well as the -l flag which displays the extra file details.

Next, we can create a new folder using the mkdir command, which stands for "Make Directory". Below we create a new folder called "testdir".

Type mkdir testdir and press <ENTER>. Then type ls and press <ENTER>. You should see your new directory in the list.

To create multiple nested directories at once, use the -p flag to create a whole chain of directories like this: mkdir -p directory1/directory2/directory3

The Command Line isn’t that useful if we can only stay in one location, so let’s learn how to browse through different directories in the file system. We can do this via the cd command, which stands for "Change Directory".

First, type cd testdir and press <ENTER>. Then type pwd and press <ENTER>. Note the output now shows that we are inside the "testdir" directory specified in the cd command. We browsed into it!

Type cd .. and press <ENTER>. The .. tells the Command Line to browse backwards to the parent directory.

Then type pwd and press <ENTER>. Note the output now shows that you are back in the original directory. We browsed backwards!

Next we’ll learn how to create a new empty file in the current directory.

Type touch newfile1.txt and press <ENTER>. You can use the ls command to see that the new file was created in the current directory.

Now we’ll copy that file from one folder to another using the cp command.

Type cp newfile1.txt testdir and press <ENTER>. Now use the ls and ls testdir commands to see that the new file still exists in the current directory and was copied to the "testdir" directory.

We can also move files instead of copying using the mv command.

Type touch newfile2.txt and press <ENTER> to create a new file. Next, type mv newfile2.txt testdir and press <ENTER> to move the file into the "testdir" folder.

Use the ls and ls testdir commands to confirm that the file has been moved into the "testdir" folder (it should no longer appear in the original location you created it, since it was moved not copied).

The mv command can also be used to rename files.

To do that, type touch newfile3.txt and press <ENTER> to create a new file. Then type mv newfile3.txt cheese.txt and press <ENTER> to update the file’s name. Use ls to confirm that the filed was renamed.

Finally, we can delete files and folders using the rm command.

Type rm cheese.txt and press <ENTER> to remove the file. Use ls to confirm the file was removed.

Type rm -rf testdir and press <ENTER> to remove the "testdir" directory and its contents. Use ls to confirm the directory was removed.

Note that we need to use the -rf flags when removing directories. This forces the removal of the folder and all of its contents.

5) Build Up Your Text Editor Skills with Vim

At this point, we’ve covered the basics of the Command Line and seen a few examples of how we can work with files without a mouse.

Although we now know how to create, copy, move, rename, and delete files from the Command Line, we haven’t seen how we edit the content of text files in the terminal.

Working with text files in the terminal is important because computer code is nothing more than text saved in an organized set of files.

Sure we could use a fancy text editor like Microsoft Word (or more likely specialized code editors like Sublime or Atom) to write and edit our code, but this is not required. The terminal is often the most convenient place to write and edit code since we usually already have it open to run commands!

There are several excellent text editors created specifically for this purpose, and I recommend learning the basics of one called Vim .

Vim is one of the oldest text editors around and it is a time-tested gem. Vim stands for " VI i M proved" since it is the successor to a tool called Vi .

As mentioned, Vim is a text editor that was built to run directly in the terminal, so we don’t need to open a separate window to work in or use a mouse at all. Vim has a set of commands and modes that allow us to conveniently create and edit text content using only the keyboard.

Vim does have bit of a learning curve , but with a little bit of practice, the skills you learn will pay dividends throughout your coding career.

Vim is installed by default on many operating systems. To check if it’s installed on your computer, open the Command Line and type vim -v .

If Vim opens in your terminal and shows the version, you’re good to go! If not, you’ll need to install it on your system. (Note that you can quit Vim by typing :q! and pressing <ENTER>). For more information on installing Vim, see https://www.vim.org.

In my opinion, the quickest and easiest way to learn how to use Vim is to use their built-in tutorial, the VimTutor . To run it, ensure that Vim is installed on your system, open the Command Line, type vimtutor , and press <ENTER>.

It is such a good tutorial that there is no reason for me to waste time trying to explain it here. So go do the VimTutor, like now! See you in the next section.

If you still have energy left after you've completed the VimTutor, check out these 7 Vim commands that will dramatically improve your productivity as you get started with Vim.

6) Take-up Some HTML

You can think of HTML – short for H yper T ext M arkup L anguage – as the bones of a web page. It determines the structure of the page by specifying the elements that should be displayed and the order that they should be displayed in.

Every web page that you’ve ever visited in your browser has some HTML associated with it. When you visit a web page, the web server hosting the web page sends over some HTML to your browser. Your browser then reads it and displays it for you.

Most web pages contain a fairly standard set of content, including a title, text content, links to images, navigation links, headers and footers, and more. All of this information is stored as HTML that defines the structure of the page.

One thing to keep in mind is that HTML is not technically a programming language, although it is often referred to as "HTML code".

As we’ll see later, other programming languages enable us to write code that does stuff , such as running a set of instructions in sequence. HTML doesn’t do anything. We don’t run or execute HTML. HTML just sits there in a file and waits to be sent to a web browser which will display it to the end-user.

In fact, HTML is basically just data. It is data that defines what a web page should look like, nothing more.

So how do you write HTML? HTML uses a standard set of tags (basically just labels) to identify the available elements that make up a web page. Each tag is defined using angle brackets.

For example, the title tag is defined as <title>My Page Title</title> and the paragraph tag is defined as <p>A bunch of random text content.</p> .

Each HTML element is made up of a starting tag and an ending tag. The starting tag is just the tag label in between angle brackets, like this:

<tagname>

This opens the new HTML tag. The ending tag is essentially the same, but it uses a forward slash after the first angle bracket, to mark it as an ending tag:

</tagname>

Any text between the two tags is the actual content that the page will display.

Let’s cover a couple of the most common tags in use. The first is the <html> tag. This defines the start of an HTML page. A corresponding </html> tag (note the forward slash) defines the end of the HTML page. Any content between these tags will be a part of the page.

The second is the <head> tag. This defines additional information that the browser will use to understand the page. Most of the content in this tag is not displayed to the user. A corresponding </head> tag defines the end of the HEAD section.

Previously, we saw the <title> tag. It defines the title of the web page, which the browser will display in the browser tab. This tag needs to be placed inside the <head>...</head> section.

Next is the <body> tag. All content inside this tag makes up the main content of the web page. Putting these four tags together looks something like this:

The simple HTML snippet above represents a simple web page with a title and a single paragraph as body content.

This example brings up a point we didn’t mention in the last section. HTML tags can be nested inside each other. This just means that HTML tags can be placed inside other HTML tags.

HTML provides many other tags to provide a rich set of content to web users. We won't cover them in detail here, but below is a short list for reference:

• <p> : A paragraph of text starting on a new line.
• <h1> : A page heading usually used for page titles.
• <h2> : A section heading usually used for section titles.
• <hx> : Where x is a number between 3 and 6, for smaller headings.
• <img> : An image.
• <a> : A link.
• <form> : A form containing fields or inputs for a user to fill out and submit.
• <input> : An input field for users to enter information, usually within a form.
• <div> : A content division, used to group together several other elements for spacing purposes.
• <span> : Another grouping element, but used to wrap text phrases within another element, usually to apply specific formatting to only a specific part of the text content.

7) Tackle Some CSS

A web page without CSS – or C ascading S tyle S heets – is like a cake without frosting. A frosting-less cake serves its purpose, but it doesn’t look appetizing!

CSS allows us to associate style properties such as background color, font size, width, height, and more with our HTML elements.

Each style property tells the browser to render the desired effect on the screen. Like HTML, CSS is not technically a programming language. It doesn’t let us perform actions, it simply lets us add styles to bare bones HTML.

Let’s see how to associate CSS styles with our HTML elements. There are three pieces to this puzzle:

The CSS selector: Used to identify the HTML element or elements we want the style to apply to.

The CSS property name: The name of the specific style property that we want to add to the matched HTML elements.

The CSS property value: The value of the style property we want to apply.

Here is an example of how these pieces come together to set the color and font size of a paragraph:

Let’s start at the beginning, before the curly braces. This is where the CSS selector goes. In this case, it is the letter p which indicates the <p> (paragraph) HTML tag. This means that the styles inside the curly braces will apply to all <p> tags on the web page.

Let’s move on to what goes inside the curly braces – the styles we want to apply to the targeted elements.

Here we find pairs of CSS properties and values, separated by a colon. The properties (in this case "color" and "font-size") are on the left. The values of these properties (in this case "red" "12px") are on the right. A semicolon ends each property/value pair.

You can probably see how this works. The snippets of CSS code above tell the browser to use red, 12px size letters for all the text placed inside <p> tags.

So how does an HTML page know to include these CSS styles? Enter the <link> HTML tag. Usually, CSS styles are created in separate files ( .css files) from the HTML. This means we need some way to import them into our HTML files so the browser knows that the styles exist.

The <link> element exists for this purpose. We include <link> elements in the <head> section of HTML files which allow us to specify the external CSS files to import:

In this example, we are importing the CSS styles specified by the href attribute, in this case the file /home/style.css .

In the next 3 sections, we'll (finally) dive into some more technical programming languages!

We'll go over a general overview of JavaScript, Python, and Java, as well as walk through some of the essential coding concepts common to the 3 languages. We will compare and contrast the language features and example code so you can hopefully get a well-rounded understanding of the basics of all three.

8) Start Programming with JavaScript

Let’s start by answering the following question: if we can use HTML to build the structure of a web page and CSS to make it look pretty, why do we need JavaScript?

The answer is that we technically don’t. If we are happy with a static site that sits there and looks pretty, we are good to go with just HTML and CSS.

The keyword here is "static". If, however, we want to add dynamic features to our web pages, such as changing content and more complex user interactions, we need to use JavaScript.

What is JavaScript?

So what exactly is JavaScript? JavaScript is a programming language that was created specifically for websites and the Internet. As we mentioned in section 2, most programming languages are either compiled or interpreted, and programs are typically run in a standalone manner.

JavaScript is somewhat unique in this respect in that it was designed to be executed directly inside web browsers. It allows us to write code representing sets of actions that will be executed on our web pages to make our sites much more dynamic.

You can either write JavaScript code in text files named with a .js extension or inside <script> tags directly in the HTML.

For many years, JavaScript code was primarily relegated to running inside web browsers. But the Node.js project changed this paradigm by creating a standalone JavaScript environment that could run anywhere.

Instead of being trapped in a browser (that is, client-side), Node.js can be installed locally on any computer to allow the development and execution of JavaScript code. You can also install Node on web servers which allows you to use JavaScript as backend code for applications instead of simply as web browser frontend code.

Now that we've covered some background, let's dive into a few basics of the JavaScript language.

Variables and Assignment in JavaScript

Variables possibly represent the most fundamental concept in programming. A variable is simply a name or placeholder that is used to reference a particular value.

The word variable implies that the stored value can change throughout the execution of the program.

You can use variables to store numbers, strings of text characters, lists, and other data structures that we will talk more about in a minute.

All programming languages use variables, but the syntax varies between different languages.

Variables are useful since we can reference their values throughout our code. This enables us to check their values as needed and perform different actions depending on how the variable’s value changes.

In JavaScript, we declare variables using the let keyword, like this: let x; .

This declares x as a variable that we can use in our code. Note that we added a semicolon at the end of the line. In JavaScript (and many other languages) semicolons are used to specify the end of each code statement.

Now that we have created the variable x , we can assign a value to it using the equals sign, also called the assignment operator : x = 10;

Here we assigned the number 10 to the variable named x . Now any time we use x in our code, the value 10 will be substituted in.

Both variable declaration and assignment can be done in one line as follows:

Data Types in JavaScript

In the last section, we stored an integer (whole number) value in the variable named x . You can also store decimal numbers, or floating-point numbers as they are known. For example, we could write: let x = 6.6; .

The different types of values we can store in variables are called data types . So far we have only seen numeric data types (integers and floating-point numbers), but we are just scratching the surface. We can store text data in variables as well.

In coding terminology, a piece of text is called a string . We can store a string value in our variable x by surrounding it in either single or double quotes:

The next data type we’ll discuss is the boolean . A boolean can only hold one of two values, true or false – and they must be all lowercase. In JavaScript, true and false are two keywords used specifically as values for boolean variables:

Note that the values true and false don’t appear within quotes the way strings do. If we surround them with quotes, the values would be strings, not booleans.

We often use booleans to control the flow of programs in conditional (if/else) statements which we’ll learn about next.

Program Flow Control Statements in JavaScript

Now that we have an understanding of variables and the basic JavaScript data types, let’s take a look at some things we can do with them.

Variables aren't that useful without being able to tell our code to do something with them. We can make our variables do things by using statements .

Statements are special keywords that allow us to perform some action in our code, often based on the value of a variable we have defined. Statements let us define the logical flow of our programs, as well as perform many useful actions that will dictate how our programs work.

If / Else Statement

The first statement we’ll discuss is the if statement. The if statement allows us to perform some action only when a desired condition is true. Here is how it works:

We defined a variable called x and set its value to 10. Then comes our if statement. After the keyword if , we have a set of parentheses containing the condition to evaluate, in this case, x > 5 . We just defined x to equal 10, so we know that this condition is true in this example.

Since the condition in the parentheses is true, the code between the curly braces will be executed, and we will see the string "X is GREATER than 5!" printed to the screen. (We didn't discuss the meaning of console.log() , so for now just know that it prints the value in the parentheses to the screen).

In the same example, we also included an else statement. This allows us to execute specific code in the event that the condition in the condition is false .

While Loops

The next type of statement we’ll discuss is the while loop . Loops enable us to repeat a block of code as many times as we desire, without copying and pasting the code over and over again.

For example, let’s assume we need to print a sentence to the screen 5 times. We could do it like this:

This works fine for only 5 messages, but what about 100, or 1000? We need a better way to repeat pieces of code multiple times, and loops allow us to do this. In coding terminology, repeating a piece of code multiple times is called iteration.

This following while loop will continue running the block of code inside it as long as the specified condition remains true:

In this example, we initialize x to the value of 1. Then we write a while loop. Similar to the if statement, we add a condition in parentheses. In this case the condition is x <= 100 . This condition will be true as long as x is less than or equal to 100.

Next we specify the block of code to execute in the curly braces. First, we print out our message to the console. Then we increment x by 1.

At this point the loop attempts to re-evaluate the condition to see if it’s still true . Variable x now has a value of 2 since it was incremented in the first loop run. The condition is still true since 2 is less than 100.

The code in the loop repeats until x gets incremented to the value of 101. At this point, x is greater than 100 so the condition is now false , and the code in the loop stops executing.

The HTML <script> Tag

Now that we’ve introduced JavaScript, let’s discuss how to add JavaScript code files into an HTML page. We can do this using an HTML tag that we haven’t discussed yet – the <script> tag.

This is similar to the <link> element that we used to add CSS files to our HTML, except that the <script> element is specifically for JavaScript.

Let’s say we saved one of the previous JavaScript examples we discussed in a file called customscript.js in the same folder as our HTML file. We can add this JavaScript file to our HTML by adding the following HTML tag into the <head>...</head> section of our HTML:

This will load in the JavaScript code from the file, which will execute when the web page is displayed in the browser.

Once you get comfortable with your JavaScript skills, you can try building some of these fun beginner-friendly projects to practice.

9) Continue Programming with Python

Now that you've learned some basic JavaScript, it will be useful to jump into another programming language – Python.

Many programming languages provide a similar set of functionality, including variables, arithmetic operators, if/else statements, loops, and functions.

It's helpful to see how different programming languages implement similar features. The concepts are usually very similar, but the syntax (the way the code is written) varies from language to language.

What is Python?

First we’ll cover a little bit of background information on Python. Like JavaScript, Python is a high- level programming language that prioritizes ease of development over the speed of execution.

In my opinion, Python is one of the best languages for beginners to learn. The syntax is clean and intuitive and it is a very popular language in the open-source and business spheres.

Earlier we talked about compiled languages versus interpreted languages. Python is an interpreted language. Each time we want to run a Python program, the Python interpreter actively processes your code and executes it line by line on your machine.

This is different than compiled languages, in which we would first use a compiler to process the code into a more optimized form (an executable), and then execute it later.

Unlike JavaScript, Python was not built to be run directly inside web browsers. Python was created to be a convenient scripting language – a language that can be used to write code for arbitrary tasks that usually execute on a user’s local computer.

Python code can be executed on any computer that has the Python interpreter installed on it. It is still a commonly used scripting language but is also used extensively for data science and server-side applications.

Variables and Assignment in Python

Like JavaScript, Python allows us to define variables. In Python we can simply use the equals sign to create and assign variables as needed:

There are two differences between the syntax for defining variables in Python and JavaScript. In Python, we don’t need the let keyword and we also don’t need a semi-colon at the end of each line.

Python uses a set of syntax rules based off of whitespace and indentation. This removes the need for line terminating characters like the semi-colon, and block scoping using curly braces.

Data Types in Python

Python also has a set of data types that we can assign to our variables. These include integers, floating-point numbers (decimals), strings, lists, and dictionaries.

Integers, floating-point numbers, and strings are essentially the same as their JavaScript counterparts, so we won’t repeat that information here.

In Python, booleans are very similar to those in JavaScript, except that the keywords True and False must be capitalized:

Program Flow Control Statements

Like in JavaScript, Python has as similar set of flow control statements, but with slightly different syntax.

This is the Python equivalent of the if/else example we saw in the JavaScript section:

We defined a variable called x and set its value to 10, followed by our if statement. Since the condition in the parentheses evaluates to True , the code indented after the if statement will be executed, and we will see the string 'X is GREATER than 5!' printed to the screen.

In Python, we use the print() function for printing information to the screen.

Also note the else statement above, which will print an alternative string to the screen if x if the condition is False .

There are two main differences between the Python code above and the JavaScript code we saw previously. Python uses a colon instead of curly braces to indicate the beginning of the if statement block.

In addition, the indentation of the print() function actually matters in Python. In JavaScript, the indentation or white space between statements doesn’t matter since JavaScript identifies code blocks using curly braces and identifies the end of a statement using a semi-colon. But in this Python example, there are no semi-colons and no curly braces!

That is because Python actually uses the white space and newline characters to identify the end of statements and code blocks.

The colon tells the Python interpreter that the if block is starting. The code that makes up the if block must be indented (1 tab = 4 spaces is the convention) for the Python interpreter to know that it is a part of the if block. The next unindented line will signal the end of the if block.

Next we’ll discuss loops in Python. The while loop in Python is essentially the same as we saw in JavaScript, but with the Python syntax:

The differences between this while loop and the JavaScript version are that:

• We removed the let when defining our variables.
• We removed line-ending semicolons.
• We replaced the curly braces with a colon.
• We made sure that the code in the loop is indented with a tab.

We printed an additional message outside of the loop to show that unindented lines of code are not a part of the loop and won't be repeated.

For beginner Pythonistas, I recommend taking a peek at the Zen of Python , which is a list of 20 rules-of-thumb for writing Pythonic code.

And when you get comfortable with the basics, try building some of these fun beginner-friendly Python projects .

10) Further Your Knowledge with Java

Now that we’ve worked with a couple of higher-level programming languages, let’s take it one step lower with Java.

Unlike JavaScript and Python which execute source code in real time using an interpreter, Java is a compiled language. This means a compiler is used (instead of an interpreter) to convert Java source code into a form the computer can understand.

Most compilers generate one or more executable files made up of machine code that are ready to run on the specific operating system and hardware platform they were compiled for.

But Java is somewhat special in that it compiles the Java source code into an intermediate form called bytecode . This is different than the machine code that most other compiled languages produce. Java bytecode is intended to be executed by something called the Java Virtual Machine (JVM) .

You can think of the JVM as a program that you install on your computer, which allows you to run Java programs by executing Java bytecode. When people talk about " whether or not Java is installed on a computer ," they are usually asking whether or not the JVM is installed on the computer.

The JVM serves a similar function to the interpreters we discussed in previous chapters. But instead of taking source code (which is stored in .java files) as an input, it takes compiled bytecode.

The benefit of this setup is that it allows bytecode compiled on particular operating systems and platforms to be executed by a JVM on any other platform.

For example, imagine we have a file of Java code that was written and compiled to bytecode on a computer running the Windows operating system. This bytecode can be executed (that is, the program can be run) by a JVM on any platform, including Windows, Mac OS, Linux, and so on.

This is not the case with most compiled executables in other programming languages, which can only execute in the environment which they were compiled for.

Variables and Assignment in Java

One major difference between Java and the languages we have seen so far (Python and JavaScript) is that Java is a statically typed language.

This means that the data types of our variables must be known and established at the time the program is compiled.

Each time we create a variable in Java code, we need to explicitly specify the data type of that variable, such as an integer, string, and so on. This is called variable declaration .

Once we declare a variable’s data type, it can only hold that type of data throughout the execution of the program.

This is very different from JavaScript and Python, where variable data types are established during program execution, also known as run time . Languages like JavaScript and Python are therefore referred to as dynamically typed languages – we don’t explicitly state variable data types in our source code and can easily reassign a variable to any type on the fly.

In Java, we create variables using this syntax:

Here the Datatype is the type of data that the variable will store, such as Integer, String, and so on. Next, the name represents the name of the variable we are defining so we can use it in our code. The value is the actual value we are assigning to the variable. Note that like JavaScript, all Java statements end in a semicolon.

Data Types in Java

In Java, the basic built-in data types are called the primitive data types and they will look very familiar based on what we have seen in higher-level languages like Python and JavaScript. The main primitive types are:

• Integer int : Stores whole numbers between −2,147,483,648 and 2,147,483,647.
• Float float : Stores decimal numbers between -3.4x10^38 to -1.4x10^-45 for negative values, 1.4x10^-45 to 3.4x10^38 for positive values.
• Boolean bool : Stores one of the two boolean values true or false .

Note that there are a few other primitive types (short, long, byte, and double) that we won’t be covering here since they aren’t used as often as the others. Here is how we initialize these data types:

Integer: int x = 100;

Float: float pi = 3.14;

Char: char middleInitial = 'T';

Boolean: bool isHuman = true;

I do want to reiterate that once the data type of a variable is declared, that variable can only hold values of the specified data type.

For example, an error would be thrown if our program tried to store a character value inside a variable that was declared to be an integer. We can’t assign the character 'S' to the integer variable x in the previous example.

The next data type we’ll discuss is the string – a sequence of characters, numbers, or symbols represented as textual data.

Strings in Java are a non-primitive data type, which means they are built up from smaller parts. To declare a string variable we use the String data type and place the assigned value in double-quotes:

Program Flow Control Statements in Java

Like JavaScript, Java uses curly braces to define code blocks for if statements, loops, and functions. We’ll examine the same program control statements as in the previous chapters and update the examples to use the Java syntax.

Here is the Java if/else statement that mirrors the examples in the previous sections:

This basic if example is almost identical to the JavaScript version. The only differences are we declared the datatype of x to be int and we using System.out.println() instead of console.log() to print out our message.

Next, we’ll move on to loops in Java. Since Java and JavaScript syntax are quite similar, the while loop in Java is essentially the same as we saw in JavaScript:

This while loop will print out the specified message 100 times.

This concludes our sections on specific programming languages. It may have been a bit repetitive since we covered the same set of concepts in 3 languages, but hopefully this helped hammer in these basic but fundamental ideas.

Now we'll round out this article with a few in-between topics that you might not otherwise start learning right away.

We'll talk about an essential collaboration tool called Git. Then we'll learn to store and access data in a database. Next we'l briefly touch on Web development frameworks, and finally we'll shed some light on package managers.

11) Track Your Code Using Git

Git is the most popular Version Control System (VCS) in use today. It allows multiple developers to collaborate on software together. In this section we’ll learn what Git is, how it works, and how to use its basic commands.

Before jumping straight into Git, let’s flesh out some concepts common to most programming projects.

The full set of directories and files that make up a software project is called a codebase . The project root is the highest-level folder in the project’s directory tree. Code files can be included directly in the project root or organized into multiple levels of folders.

When the codebase is ready for testing or deployment it can be built into the program that will run on your computer. The build process can include one or more steps that convert the code written by humans into an executable that can be run on your computer’s processing chips.

Once the code is built, your program is ready to run on your specific operating system, such as Linux, Mac OS, or Windows.

Over time, developers update the project code to add new features, fix bugs, implement security updates, and more. In general, there are three ways developers can make these changes to a software project:

• Add new files and folders to the project
• Edit the code in existing files and folders
• Delete existing files and folders

As projects grow and new features are added, the number of files and folders (as well as the amount of code within them) increases. Large projects can grow up to hundreds of thousands of files containing millions of lines of code.

To support this growth, the number of developers on large project teams typically increases. Large software projects can have hundreds or even thousands of developers all working in tandem.

This begs the question: " How the heck do all these developers, who may be geographically spread out all around the world, keep track of their software project code in such a way that they can work together on a single project? "

Development teams need a way to keep track of exactly what changes were made to the code, which files or folders were affected, and who made each change. Each developer also needs to be able to obtain updates from all other developers.

This process is called versioning or version control . Developers use special tools called Version Control Systems (VCS) to track, manage, and share the versions of software projects. Here are a few popular version control systems that are actively used these days:

• Subversion (SVN)
• Mercurial (Hg)

However, Git has won the crown as the go-to VCS of the day. It is by far the most popular VCS in use by government, commercial, and open-source communities worldwide.

Git forms the core of popular web-based VCS platforms like GitHub and Bitbucket. Git is an essential tool for any well-rounded developer to add to their skill set.

Basic Git Commands

Git creates and stores information about our software projects in something called a Git repository . A Git repository is just a hidden folder on your computer that Git uses to store data about the code files in a software project.

Each software project we work on typically has its own Git repository for storing information related to that project. This way, code related to different projects on a single computer can be tracked separately.

There are two main ways to create a Git repository on your computer. The first is to create a brand new Git repository in an existing folder on your file system.

To do this, simply open up the Command Line, create a new folder somewhere convenient like on your Desktop, and browse into it:

Now that we created a new folder and browsed into it, we can initialize a new Git repository using the command:

You should see some output similar to the following:

All of the Git commands we’ll run start with the word git followed by a space and then the specific Git command we would like to run. Sometimes we’ll add flags and arguments after the Git commands as well.

The git init command creates a hidden folder called .git in the current directory. This folder is the Git repository we mentioned above. You can see this by running the command ls -al .

The second way to get a Git repository on to your computer is to download one from somewhere else, like Bitbucket or GitHub.

Bitbucket and Github are websites that allow people to host open source projects that can be downloaded to your computer.

If you browse to a project you find interesting on Bitbucket or GitHub, you’ll see a button labeled Clone. This button will provide you a command and URL that you can copy and paste into the command line terminal. It will look something like this:

The git clone command downloads the repository from the specified URL into a new folder on your computer. The URL can either be a web URL as in the example above or an SSH URL as follows:

After running the git clone command, you should see a new folder created. If you browse into it, you’ll see all of the files and subfolders that make up the project you downloaded.

The next command we'll mention is git add <filename.ext> . The git add command is used to tell Git which files we want it to track, and to add changes in already tracked files to Git's staging area .

Once new or changes files have been staged, they can be committed to the repository by using the command git commit -m "Commit message" . This will store the changes in all staged files in the Git repository.

The git status and git log commands are handy for reviewing the current state of the working directory and the commit history of your project.

We barely scratched the surface here. Git has many more essential commands which are definitely worth getting comfortable with.

12) Store Data Using Databases and SQL

A database is a program specifically designed to efficiently store, update, retrieve, and delete large amounts of data. In a nutshell, we can think of a database as a container for a set of tables.

You have probably worked with tables in Microsoft Excel. A table is just a set of columns and rows containing data. We can set up tables in a database to store the information that our programs need to work properly.

Whether we are writing programs in JavaScript, Python, Java, or some other language, we can tell our programs to interact with databases as needed.

We can retrieve data from the database to display to our users on a web page. We can accept a web sign-up form from a user and store that user’s information in a database for later use.

Our programs can interact with databases in real-time as events transpire in our application. To do this, most databases speak a language called SQL , short for Structured Query Language .

SQL is a programming language specifically created for databases. It allows us to tell databases what to do.

A chunk of SQL code is called a query . We can write SQL queries to fetch the data we need at a particular time or to insert new data into a specific table. Roughly speaking there are two main types of SQL queries: read-SQL and write-SQL .

A read-SQL query is one that simply fetches data from the database for us to see or use. It doesn’t change the data in the database at all.

On the other hand, a write-SQL query either inserts new data into a table, updates existing data, or deletes existing data. We’ll learn how to write some basic read-SQL queries in this section.

Before writing a query, it helps to know what we are querying! Traditional databases contain tables made up of columns and rows. When we write a read-SQL query, our goal is usually to retrieve a subset of those rows and columns.

For example, let's say we have a table called PERSON with 4 columns, FIRST_NAME and LAST_NAME . We can use the following query to select all the data from only the FIRST_NAME column:

The SELECT keyword tells the database that we want to retrieve data. It is followed by the name of the column – FIRST_NAME – that we want to get.

Then we use the FROM keyword to tell the database which table we want to get the data from, in this case, the PERSON table. Also, note that all SQL commands are terminated by a semi-colon.

One of the most common requirements we have with data is to filter it. Filtering means restricting the result set based on a specified condition.

For example, we might only want to select rows from the PERSON table for people who are named "PHIL". We can apply filters in SQL queries using the WHERE keyword:

This query would return all columns in the PERSON table since we used an asterisk * in the SELECT clause instead of listing specific column names. Only rows in the PERSON table where the FIRST_NAME is set to "PHIL" would be retrieved.

Lastly, we’ll talk about sorting. There are many times when we’d like to see our query results sorted in a particular order. We can use the ORDER BY clause for this:

This will return all columns in the PERSON table sorted alphabetically by last name.

By default, the results will be sorted in ascending order, from A to Z. We can add the optional ASC or DESC keyword, to specify whether to sort in ascending or descending order:

13) Read About Web Frameworks and MVC

Oftentimes, we’ll find ourselves writing code for very common types of applications. Web applications (or web apps ) are applications that rely on the Internet in order to function. Webapps are some of the most commonly created types of software applications.

A web app is essentially a more functional and robust version of a website. Most web apps implement some backend code that resides on a web server and performs logic behind the scenes to support the application’s functionality.

Common programming languages to use for a web app’s backend code include Python, Java, and JavaScript, among others.

Some functionalities common to most web apps include:

• Providing a convenient way to dynamically alter content on web pages
• Performing secure user authentication via a login page
• Providing robust application security features
• Reading and writing data to a database

A web framework is a set of code libraries that contain the common functionalities that all web apps use out of the box. Web frameworks provide a system for developers to build their applications without having to worry about writing the code for many of the behind the scenes tasks common to all web apps.

We only need to utilize the parts of the framework that meet the needs of our web app.

For example, if we don’t need to connect to a database in a particular web app, we can just ignore the database features and use the other features that we do need.

We still have the full ability to customize the web pages that make up our application, the user flow, and the business logic. You can think of a web framework as a programming tool suite that we can use to build web apps.

Each programming language we covered in this article has one or more popular web frameworks currently in use. This is great because it gives development teams the flexibility to use the framework of the language that they are the most proficient in.

Java has the Spring Framework that's made especially convenient via Spring Boot . Python has the Django Framework . JavaScript has the Node.js runtime environment with the multiple framework options including Express.js and Meteor.js . These frameworks are all free and open-source.

14) Play with Package Managers

The final topic that we’ll cover in this guidebook is the package manager . Depending on the context, a package can either represent a standalone program that is ready to install on a computer or an external code library that we want to leverage in one of our software projects.

Since our applications often depend on these external code libraries, we also refer to them as dependencies .

A package manager is a program that helps us maintain the dependencies of a system or software project. By "maintain" we mean installing, updating, listing, and uninstalling the dependencies as needed.

Depending on the context, the package managers we’ll discuss can either be used to maintain the programs we have installed on our operating systems or to maintain the dependencies of a software project.

Mac OS X: Homebrew

Homebrew is the most popular package manager for the Mac OS X operating system. It offers a convenient way to install, update, track, list, and uninstall packages and applications on your Mac.

Many applications that can be installed via downloaded .dmg files can also be downloaded and installed using Homebrew.

Here is an example of installing the wget package via Homebrew:

Linux: Apt and Yum

Since Linux was built around the Command Line, it’s no surprise that package managers are the default way to install programs.

Most mainstream flavors of Linux ship with a built-in package manager. Advanced Package Tool (APT) is the native package manager for Debian and Ubuntu-based Linux distributions. Yellowdog Updater, Modified (YUM) is the native package manager for the RedHat Linux distribution.

Here is an example of installing Vim using APT:

And using Yum:

JavaScript: Node Package Manager (NPM)

Now that we have seen how some OS-level package managers work, let’s take a look at some programming language-specific package managers. These can help us manage the software libraries that many of our coding projects depend on. Node Package Manager (NPM) is installed by default with Node.js.

One difference between NPM and the previous package managers we have seen is that NPM can be run in local or global mode. Local mode is used to install a package only within a particular project/directory we are working on, while global mode is used to install the package on the system.

By default, packages are installed locally, but you can use the -g flag to install a package globally:

Python: Pip

Python also has a package manager called Pip . Pip may already be installed on your system as it comes prepackaged with recent versions of Python. Pip allows us to easily install packages from the Python Package Index using the pip install <package-name> command:

Java: Apache Maven

Apache Maven (usually referred to as simply Maven ) is a free and open-source tool suite that includes dependency management.

Maven is mostly used for Java projects although it does support other languages as well. Maven usage is a bit more complicated and it can do a lot of things, so we won't get into the weeds here.

In this article, I introduced a set of essential coding concepts and tools with the intention of presenting a bird’s eye view of software development that I wish I had when I started learning to code.

I covered topics including the Internet, several programming languages, version control systems, and databases with the goal of describing how these pieces of the puzzle fit together.

If you enjoyed this article, I wrote a book called the Coding Essentials Guidebook for Developers which has 14 chapters, each covering one of the topics discussed in this post.

In the book I go into even more depth on these 14 subjects, so that might be a good resource for you to check out if you got value out of this article.

After reading this, you may feel drawn to a particular language, tool, or concept. If this is the case I encourage you to dive deeper into that area to further your learning.

If you have any questions, suggestions, or concerns about this book, I would love to hear from you at [email protected] .

Read more posts .

If you read this far, thank the author to show them you care. Say Thanks

Learn to code for free. freeCodeCamp's open source curriculum has helped more than 40,000 people get jobs as developers. Get started

• History & Society
• Science & Tech
• Biographies
• Animals & Nature
• Geography & Travel
• Arts & Culture
• Games & Quizzes
• On This Day
• One Good Fact
• New Articles
• Lifestyles & Social Issues
• Philosophy & Religion
• Politics, Law & Government
• World History
• Health & Medicine
• Browse Biographies
• Birds, Reptiles & Other Vertebrates
• Bugs, Mollusks & Other Invertebrates
• Environment
• Fossils & Geologic Time
• Entertainment & Pop Culture
• Sports & Recreation
• Visual Arts
• Demystified
• Image Galleries
• Infographics
• Top Questions
• Britannica Kids
• Saving Earth
• Space Next 50
• Student Center
• Introduction

Machine and assembly languages

• Visual Basic
• Declarative languages
• Scripting languages
• Web scripting
• Control structures
• Data structures

computer programming language

Our editors will review what you’ve submitted and determine whether to revise the article.

• Open Library Publishing Platform - Digital Humanities Tools and Techniques I - An introduction to and and overview of computer programming languages
• Computer Science at Brown University - A History of Computer Programming Languages
• IEEE Computer Sociey - Coding From 1849 to 2022: a Guide to The Timeline of Programming Languages
• Table Of Contents

computer programming language , any of various languages for expressing a set of detailed instructions for a digital computer . Such instructions can be executed directly when they are in the computer manufacturer-specific numerical form known as machine language , after a simple substitution process when expressed in a corresponding assembly language , or after translation from some “higher-level” language. Although there are many computer languages, relatively few are widely used.

Machine and assembly languages are “low-level,” requiring a programmer to manage explicitly all of a computer’s idiosyncratic features of data storage and operation. In contrast, high-level languages shield a programmer from worrying about such considerations and provide a notation that is more easily written and read by programmers.

Language types

A machine language consists of the numeric codes for the operations that a particular computer can execute directly. The codes are strings of 0s and 1s, or binary digits (“bits”), which are frequently converted both from and to hexadecimal (base 16) for human viewing and modification. Machine language instructions typically use some bits to represent operations, such as addition, and some to represent operands, or perhaps the location of the next instruction. Machine language is difficult to read and write, since it does not resemble conventional mathematical notation or human language, and its codes vary from computer to computer.

Assembly language is one level above machine language. It uses short mnemonic codes for instructions and allows the programmer to introduce names for blocks of memory that hold data. One might thus write “add pay, total” instead of “0110101100101000” for an instruction that adds two numbers.

Assembly language is designed to be easily translated into machine language. Although blocks of data may be referred to by name instead of by their machine addresses, assembly language does not provide more sophisticated means of organizing complex information. Like machine language, assembly language requires detailed knowledge of internal computer architecture . It is useful when such details are important, as in programming a computer to interact with peripheral devices (printers, scanners, storage devices, and so forth).

Algorithmic languages

Algorithmic languages are designed to express mathematical or symbolic computations. They can express algebraic operations in notation similar to mathematics and allow the use of subprograms that package commonly used operations for reuse. They were the first high-level languages.

The first important algorithmic language was FORTRAN ( for mula tran slation), designed in 1957 by an IBM team led by John Backus . It was intended for scientific computations with real numbers and collections of them organized as one- or multidimensional arrays. Its control structures included conditional IF statements, repetitive loops (so-called DO loops), and a GOTO statement that allowed nonsequential execution of program code. FORTRAN made it convenient to have subprograms for common mathematical operations, and built libraries of them.

FORTRAN was also designed to translate into efficient machine language. It was immediately successful and continues to evolve.

ALGOL ( algo rithmic l anguage) was designed by a committee of American and European computer scientists during 1958–60 for publishing algorithms , as well as for doing computations. Like LISP (described in the next section), ALGOL had recursive subprograms—procedures that could invoke themselves to solve a problem by reducing it to a smaller problem of the same kind. ALGOL introduced block structure, in which a program is composed of blocks that might contain both data and instructions and have the same structure as an entire program. Block structure became a powerful tool for building large programs out of small components.

ALGOL contributed a notation for describing the structure of a programming language, Backus–Naur Form, which in some variation became the standard tool for stating the syntax (grammar) of programming languages. ALGOL was widely used in Europe, and for many years it remained the language in which computer algorithms were published. Many important languages, such as Pascal and Ada (both described later), are its descendants.

The C programming language was developed in 1972 by Dennis Ritchie and Brian Kernighan at the AT&T Corporation for programming computer operating systems . Its capacity to structure data and programs through the composition of smaller units is comparable to that of ALGOL. It uses a compact notation and provides the programmer with the ability to operate with the addresses of data as well as with their values. This ability is important in systems programming , and C shares with assembly language the power to exploit all the features of a computer’s internal architecture. C, along with its descendant C++ , remains one of the most common languages.

Business-oriented languages

COBOL ( co mmon b usiness o riented l anguage) has been heavily used by businesses since its inception in 1959. A committee of computer manufacturers and users and U.S. government organizations established CODASYL ( Co mmittee on Da ta Sy stems and L anguages) to develop and oversee the language standard in order to ensure its portability across diverse systems.

COBOL uses an English-like notation—novel when introduced. Business computations organize and manipulate large quantities of data, and COBOL introduced the record data structure for such tasks. A record clusters heterogeneous data—such as a name, an ID number, an age, and an address—into a single unit. This contrasts with scientific languages, in which homogeneous arrays of numbers are common. Records are an important example of “chunking” data into a single object, and they appear in nearly all modern languages.

• Trending Now
• Foundational Courses
• Data Science
• Practice Problem
• Machine Learning
• System Design
• DevOps Tutorial

Assignment Operators in Programming

Assignment operators in programming are symbols used to assign values to variables. They offer shorthand notations for performing arithmetic operations and updating variable values in a single step. These operators are fundamental in most programming languages and help streamline code while improving readability.

Table of Content

What are Assignment Operators?

• Types of Assignment Operators
• Assignment Operators in C
• Assignment Operators in C++
• Assignment Operators in Java
• Assignment Operators in Python
• Assignment Operators in C#
• Assignment Operators in JavaScript
• Application of Assignment Operators

Assignment operators are used in programming to  assign values  to variables. We use an assignment operator to store and update data within a program. They enable programmers to store data in variables and manipulate that data. The most common assignment operator is the equals sign ( = ), which assigns the value on the right side of the operator to the variable on the left side.

Types of Assignment Operators:

• Simple Assignment Operator ( = )
• Addition Assignment Operator ( += )
• Subtraction Assignment Operator ( -= )
• Multiplication Assignment Operator ( *= )
• Division Assignment Operator ( /= )
• Modulus Assignment Operator ( %= )

Below is a table summarizing common assignment operators along with their symbols, description, and examples:

Assignment Operators in C:

Here are the implementation of Assignment Operator in C language:

Assignment Operators in C++:

Here are the implementation of Assignment Operator in C++ language:

Assignment Operators in Java:

Here are the implementation of Assignment Operator in java language:

Assignment Operators in Python:

Here are the implementation of Assignment Operator in python language:

Assignment Operators in C#:

Here are the implementation of Assignment Operator in C# language:

Assignment Operators in Javascript:

Here are the implementation of Assignment Operator in javascript language:

Application of Assignment Operators:

• Variable Initialization : Setting initial values to variables during declaration.
• Mathematical Operations : Combining arithmetic operations with assignment to update variable values.
• Loop Control : Updating loop variables to control loop iterations.
• Conditional Statements : Assigning different values based on conditions in conditional statements.
• Function Return Values : Storing the return values of functions in variables.
• Data Manipulation : Assigning values received from user input or retrieved from databases to variables.

Conclusion:

In conclusion, assignment operators in programming are essential tools for assigning values to variables and performing operations in a concise and efficient manner. They allow programmers to manipulate data and control the flow of their programs effectively. Understanding and using assignment operators correctly is fundamental to writing clear, efficient, and maintainable code in various programming languages.

Please Login to comment...

Similar reads.

• Programming

Improve your Coding Skills with Practice

What kind of Experience do you want to share?

Princeton University COS 217: Introduction to Programming Systems

Assignment 4: assembly language programming.

The purpose of this assignment is to help you learn about computer architecture, assembly language programming, and testing strategies. It also will give you the opportunity to learn more about the GNU/Unix programming tools, especially bash , emacs , gcc217 , and gdb for assembly language programs.

The assignment consists of two parts, each of which has subparts. We strongly encourage you to complete Part 1 by the end of the first week of the assignment period.

Part 2e, as defined below, is the "on your own" part of this assignment. That part is worth 10% of this assignment.

Part 1: A Word Counting Program in Assembly Language

Part 1a: translate to assembly language.

The Unix operating system has a command named wc ( w ord c ount). In its simplest form, wc reads characters from the standard input stream until end-of-file, and prints to the standard output stream a count of how many lines, words, and characters it has read. A word is a sequence of characters that is delimited by one or more white space characters.

Consider some examples. In the following, a space is shown as s and a newline character as n .

If the file named proverb contains these characters:

then the command:

prints this line to the standard output stream:

If the file proverb2 contains these characters:

(note that the last "line" does not end with a newline character) then the command:

prints this line to standard output:

The file mywc.c in the /u/cos217/Assignment4 directory contains a C program that implements the subset of the wc command described above. Translate that program into assembly language, thus creating a file named mywc.s . It is acceptable to use global (i.e. bss section or data section) variables in mywc.s , but we encourage you to use local (i.e. stack) variables instead. Your assembly language program should have exactly the same behavior (i.e. should write exactly the same characters to the standard output stream) as the given C program.

Part 1b: Test

Design a test plan for your mywc program. Your test plan should include tests in three categories: (1) boundary testing, (2) statement testing, and (3) stress testing.

Create text files to test your programs. Name each such file such that its prefix is mywc and its suffix is .txt . The command ls mywc*.txt should display the names of all mywc test files, and only those files.

Describe your mywc test plan in your readme file. Your description should have this structure:

mywc boundary tests:

mywc XXX .txt : Description of the characteristics of that file, and how it tests boundary conditions of your mywc program. mywc YYY .txt : Description of the characteristics of that file, and how it tests boundary conditions of your mywc program. ...

mywc statement tests:

mywc XXX .txt : Description of the characteristics of that file, and which statements of your mywc program it tests. Refer to the statements using the line numbers of the given mywc.c program. mywc YYY .txt : Description of the characteristics of that file, and which lines of your mywc program it tests. Refer to the statements using the line numbers of the given mywc.c program. ...

Your descriptions of the test files should be of the form "This file contains such-and-such characteristics, and so tests lines such-and-such of the program." Please identify the lines of code tested by line numbers. The line numbers should refer to the given C code.

mywc stress tests:

mywc XXX .txt : Description of the characteristics of that file, and how it stress tests your mywc program. mywc YYY .txt : Description of the characteristics of that file, and how it stress tests your mywc program. ...

Submit test files that contain no more than approximately 50000 characters. Submitting very large files could exhaust the course's allotted disk space on hats, and so could prohibit other students from submitting any files at all.

Submit test files that contain only printable ASCII characters. Specifically, make sure your computer-generated test files contain only characters having ASCII codes (in hexadecimal) 09, 0A, and 20 through 7E. Submitting test files that contain other characters would make it difficult for your grader to examine those files.

Finally, create a Bash shell script named testmywc to automate your mywc test plan. A Bash shell script is simply a text file that contains commands, and that has been made executable via the chmod command, for example, chmod 700 testmywc .

The testmywc script should build a mywc program from the given C code, build a mywc program from your assembly language code, execute both programs, and compare the output.

It is acceptable for your testmywc script to call other scripts that you create. Each such script should have a name that is prefixed with testmywc . The command ls testmywc* should display the names of all mywc test scripts, and only those files.

Feel free to use the testdecomment and testdecommentdiff Bash shell scripts from Assignment 1 as models.

Part 2: Beat the Compiler

Many programming environments contain modules to handle high-precision integer arithmetic. For example, the Java Development Kit (JDK) contains the BigDecimal and BigInteger classes.

The Fibonacci numbers are used often in computer science. See http://en.wikipedia.org/wiki/Fibonacci_numbers for some background information on Fibonacci numbers. Note in particular that Fibonacci numbers can be very large integers.

This part of the assignment asks you to write a minimal high-precision integer arithmetic module, and use it to compute large Fibonacci numbers.

Part 2a: Add BigInt Objects Using C Code

Suppose you must compute Fibonacci number 500000, that is, fib(500000)...

The /u/cos217/Assignment4 directory contains a C program that computes Fibonacci numbers. It consists of two modules: a client module and a BigInt ADT.

The client consists of the file fib.c . The client accepts an integer n as a command-line argument, validates it, and computes and prints fib(n) to stdout as a hexadecimal number. It prints to the standard error stream the amount of CPU time consumed while performing the computation. The client module delegates most of the work to BigInt objects.

The BigInt ADT performs high precision integer arithmetic. It is a minimal ADT; essentially it implements only an "add" operation. The BigInt ADT consists of four files:

• bigint.h is the interface. Note that the ADT makes four functions available to clients: BigInt_new , BigInt_free , BigInt_add , and BigInt_writeHex .
• bigint.c contains implementations of the BigInt_new , BigInt_free , and BigInt_writeHex functions.
• bigintadd.c contains an implementation of the BigInt_add function.
• bigintprivate.h is a "private header file" -- private in the sense that clients never use it. It allows code sharing between the two implementation files, bigint.c and bigintadd.c .

Study the given code. Then build the program with no optimization. Run the program to compute fib(500000). In your readme file note the amount of CPU time consumed.

Part 2b: Add BigInt Objects Using C Code Built with Compiler Optimization

Suppose you decide that the amount of CPU time consumed is unacceptably large. You decide to command the compiler to optimize the code that it produces...

Build the program using optimization. Specifically, specify the -D NDEBUG option so the preprocessor disables the assert macro, and the -O3 option so the compiler generates optimized code. Run the resulting program to compute fib(500000). In your readme file note the amount of CPU time consumed.

Part 2c: Add BigInt Objects Using Assembly Language Code

Suppose you decide that the amount of CPU time consumed still is too large. In an attempt to gain speed, you decide manually to code the BigInt_add function in assembly language...

Manually translate the C code in the bigintadd.c file into assembly language, thus creating the file bigintadd.s . You need not translate the code in other files into assembly language.

Your assembly language code should store all variables in memory. It should contain definitions of the BigInt_add and BigInt_larger functions; the former should call the latter, just as the C code does.

Note that assert is a parameterized macro, not a function. (See Section 14.3 of the King book for a description of parameterized macros.) So you cannot call assert from assembly language code. When translating bigintadd.c to assembly language, simply pretend that the calls of assert are not in the C code.

Build the program consisting of the files fib.c , bigint.c , and bigintadd.s using the -D NDEBUG and -O3 options. Run the program to compute fib(x) for various values of x, and make sure it writes the same output as the program built from C code does. Finally, run the program to compute fib(500000). In your readme file note the amount of CPU time consumed.

Part 2d: Add BigInt Objects Using Optimized Assembly Language Code

Suppose, to your horror, you discover that you have taken a step backward: the CPU time consumed by your assembly language code is approximately the same as that of the non-optimized compiler-generated code. So you decide to optimize your assembly language code...

Manually optimize your assembly language code in bigintadd.s , thus creating the file bigintaddopt.s . Specifically, perform these optimizations:

• Store local variables (but not parameters) in registers instead of in memory. Remember that assembly language functions must handle the EBX, ESI, and EDI registers with special care.
• "Inline" the call of the BigInt_larger function. That is, eliminate the BigInt_larger function, placing its code within the BigInt_add function.

Build the program consisting of the files fib.c , bigint.c , and bigintaddopt.s using the -D NDEBUG and -O3 options. Run the program to compute fib(x) for various values of x, and make sure it writes the same output as the program built from C code does. Finally, run the program to compute fib(500000). In your readme file note the amount of CPU time consumed.

Can you write assembly language code that is approximately as fast as the optimized code that the compiler generates? That is, can you approximately tie the compiler?

Part 2e: Add BigInt Objects Using Highly Optimized Assembly Language Code

Finally, suppose you decide to optimize your assembly language code even further, moving away from a statement-by-statement translation of C code into assembly language...

Further optimize your assembly language code in bigintaddopt.s , thus creating the file bigintaddoptopt.s . Specifically, perform these optimizations:

• Factor as much code as possible out of the loop.
• Use the assembly language loop patterns described in Section 3.6.5 of the Bryant & O'Hallaron book instead of the simpler but less efficient patterns described in precepts.
• Instead of using a uiCarry variable (stored in memory or in a register) to keep track of carries during addition, use the "carry" bit in the EFLAGS register. The carry bit is examined and set by the adcl ("add with carry long") instruction.

Feel free to implement any additional optimizations you want. However, your BigInt_add function must be a general-purpose function for adding two given BigInt objects; the function cannot be specific to the task of adding two Fibonacci numbers to generate a third Fibonacci number.

This part is difficult; we will not think unkindly of you if you decide not to do it. To do it properly you will need to learn about the adcl instruction, and about which instructions affect and do not affect the C ("carry") flag in the EFLAGS register. Hint: When writing bigintaddoptopt.s , the problem is this: How can you preserve the value of the C flag between executions of the adcl instruction? One approach to solving that problem is to determine how to save and then restore the value of the EFLAGS register. Another approach is to determine how to express the logic such that only instructions that do not affect the C flag are executed between each execution of the adcl instruction.

Build the program consisting of the files fib.c , bigint.c , and bigintaddoptopt.s using the -D NDEBUG and -O3 options. Run the program to compute fib(x) for various values of x, and make sure it writes the same output as the program built from C code does. Finally, run the program to compute fib(500000). In your readme file note the amount of CPU time consumed.

Can you beat the compiler?

Develop on hats. Use emacs to create source code. Use gdb to debug.

Do not use a C compiler to produce any of your assembly language code. Doing so would be considered an instance of academic dishonesty. Instead produce your assembly language code manually.

We encourage you to develop "flattened" C code (as described in precepts) to bridge the gap between the given "normal" C code and your assembly language code. Using flattened C code as a bridge can eliminate logic errors from your assembly language code, leaving only the possibility of translation errors.

We also encourage you to use your flattened C code as comments in your assembly language code. Such comments can clarify your assembly language code substantially.

You should submit:

• Your mywc.s file.
• Your testmywc script, and any other scripts that it calls.
• The data files that test your mywc program.
• Your bigintadd.s , bigintaddopt.s and bigintaddoptopt.s files.
• A readme file.

Your readme file should contain:

• A description of whatever help (if any) you received from others while doing the assignment, and the names of any individuals with whom you collaborated, as prescribed by the course "Policies" Web page.
• Your mywc test plan in the format specified above.
• The times consumed by the fib programs, as specified above.
• (Optionally) An indication of how much time you spent doing the assignment.
• (Optionally) Your assessment of the assignment.
• (Optionally) Any information that will help us to grade your work in the most favorable light. In particular you should describe all known bugs.

Submit your work electronically using the commands:

Please do not submit emacs backup files, that is, files that end with '~'.

As always, we will grade your work on quality from the user's and programmer's points of view. To encourage good coding practices, we will deduct points if gcc217 generates warning messages.

Comments in your assembly language programs are especially important. Each assembly language function -- especially the main function -- should have a comment that describes what the function does. Local comments within your assembly language functions are equally important. Comments copied from corresponding "flattened" C code are particularly helpful.

Your assembly language code should use .equ directives to avoid "magic numbers." In particular, you should use .equ directives to give meaningful names to:

• Enumerated constants, for example: .equ TRUE, 1 .
• Parameter stack offsets, for example: .equ OADDEND1, 8 .
• Local variable stack offsets, for example: .equ UICARRY, -4 .
• Structure field offsets, for example: .equ ILENGTH, 0 .
• Stack offsets at which callee-save registers are stored, for example: .equ EBXOFFSET, -4 .
• (In bigintaddopt.s and bigintaddoptopt.s ) Registers which are devoted to local variables, for example: .equ ISUMLENGTH, %esi .

Testing is a substantial aspect of the assignment. Approximately 10% of the grade will be based upon your mywc test plan as described in your readme file, and as implemented by your test scripts and data files.

Your grade for the "on your own" part will be based upon raw performance (How quickly does your code compute fib(500000)?) and style (Does your code contain optimizations that logically should improve performance?).

Want to create or adapt books like this? Learn more about how Pressbooks supports open publishing practices.

Assignment vs Equality

Kenneth Leroy Busbee

Assignment  sets and/or re-sets the value stored in the storage location denoted by a variable name. [1] Equality is a relational operator that tests or defines the relationship between two entities. [2]

Most control structures use a test expression that executes either selection (as in the: if then else) or iteration (as in the while; do while; or for loops) based on the truthfulness or falseness of the expression. Thus, we often talk about the Boolean expression that is controlling the structure. Within many programming languages, this expression must be a Boolean expression and is governed by a tight set of rules. However, in many programming languages, each data type can be used as a Boolean expression because each data type can be demoted into a Boolean value by using the rule/concept that zero and nothing represent false and all non-zero values represent true.

Within various languages, we have the potential added confusion of the equals symbol = as an operator that does not represent the normal math meaning of equality that we have used for most of our life. The equals symbol typically means: assignment. To get the equality concept of math we often use two equal symbols to represent the relational operator of equality. Let’s consider:

The test expression of the control structure will always be true because the expression is an assignment (not the relational operator of == ). It assigns the ‘y’ to the variable pig, then looks at the value in pig and determines that it is not zero; therefore the expression is true. And it will always be true and the else part will never be executed. This is not what the programmer had intended. The correct syntax for a Boolean expression is:

This example reminds you that you must be careful in creating your test expressions so that they are indeed a question, usually involving the relational operators. Some programming languages will generate a warning or an error when an assignment is used in a Boolean expression, and some do not.

Don’t get caught using assignment for equality.

• cnx.org: Programming Fundamentals – A Modular Structured Approach using C++
• Wikipedia: Assignment (computer science) ↵
• Wikipedia: Relational operator ↵

Programming Fundamentals Copyright © 2018 by Kenneth Leroy Busbee is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License , except where otherwise noted.

Share This Book

Academia.edu no longer supports Internet Explorer.

To browse Academia.edu and the wider internet faster and more securely, please take a few seconds to  upgrade your browser .

Enter the email address you signed up with and we'll email you a reset link.

• We're Hiring!
• Help Center

Computer Assisted Language Learning

2022, Computer Assisted Language Learning

The present work aims to elaborate a sequence of three activities using technology, a sequence which will be developed considering the theoretical approach about Computer Assisted Language Learning. The activities will be proposed as challenges for the students, so we will have challenge 1, challenge 2 and challenge 3. It is important to note that the internet has unlimited information; teachers have the role of filtering it to help students acquire and understand the use of language. In this way, teachers collaborate so that students can develop effective communication to meet their needs and help them to achieve their goals.

Related Papers

Scientife Bullettin of NamSU

Azizbek Begmatov

The article describes the specifics of learning a foreign language using computer technology, as well as the specifics of learning a foreign language using a computer and with the help of a teacher.

Dr Jose P Chiramel

Dr. Shraddha Kharade

Hojjat Namdaran

This article is mainly concerned with the use of technology as a tutor guide tool in teaching language as a second language. Since the future of our educational system is dependent on new technological products, utilizing technology found in computer-assisted language learning (CALL) has gained more importance for educators, teachers, instructors, etc. We have, thus, intended to express how computer-assisted instruction (CAI) can ease learning language, and some possible disadvantages of such technology employment that are worth consideration.

ECV: Engaging Cultures and Voices

Wayne E Arnold

"This paper will provide an overview of the broad spectrum of information concerning Computer Assisted Language Learning (CALL) and focus attention on two related areas: historical expansion of computer language programs through innovational progress and the still-present programming needs of CALL applications for further improvement of digital language resources. The rapid expansion of the internet has shifted the direction of CALL research so that now new designs are taking to task the benefits of implementing websites, online wikis, and chat programs. I explain why the efforts of CALL programmers have shifted to construct online environments geared to help students overcome many of the initial inhibitions which occur during the SLA process. Finally, due to the multiplicity of platforms available, there is an increasing demand for standards across the different CALL applications."

The Modern Language Journal

claire kramsch

languageinindia.com

Dr. Atef O AbuSa'aleek , Ali Farhan

Loading Preview

Sorry, preview is currently unavailable. You can download the paper by clicking the button above.

RELATED PAPERS

HOW, a Journal of Colombian Teachers of English

Jorge E Benavides B.

Silvia Ciornei

Glenn Stockwell

Erdinç Aslan

Language, Learning and Technology

Greg Kessler

IOLC Conference

Hayo Reinders

Ivonne londono

Andrea Tick

Education and Linguistics Research

Javed Mirani

International Journal of English Studies

International Journal of English Studies (IJES) , Pascual Cantos

GIST – Education and Learning Research Journal

Saieed Moslemie Nezhad Arani

Hassan Soleimani

accounts ziraf

Meritxell Gonzalez

Edgar R Eslit

Rebecca Wilson

Pixel-Bit, Revista de Medios y Educación

Dara Tafazoli

Pixel-Bit. Revista de Medios y Educación.

PIXEL-BIT. Revista de Medios y Educación

Dr Yashpal D Netragaonkar

Zafer Konakli

Faculty of Education, Assiut University, Egypt

Dr Mahmoud M S Abdallah

Challenges to CAL

naseer ahmed

RELATED TOPICS

•   We're Hiring!
•   Help Center
• Find new research papers in:
• Health Sciences
• Earth Sciences
• Cognitive Science
• Mathematics
• Computer Science
• Academia ©2024

Introduction to Computer Organization: ARM Assembly Language Using the Raspberry Pi

Robert G. Plantz

Section 11.2 The Assignment Operator

The C/C++ assignment operator, ‘ = ’, causes the expression on the right-hand side of the operator to be evaluated and the result to be associated with the variable that is named on the left-hand side. Subsequent uses of the variable name in the program will evaluate to this same value. For example,

will assign the integer \(123\) to the variable x . If x is later used in an expression, the value assigned to x will be used in evaluating the expression. For example, the expression

would evaluate to \(246\text{.}\)

We now explore what assignment means at the assembly language level. The variable declaration,

causes a location to be allocated and that location to be given the name “ x .” That is, other parts of the program can refer to the location where the value of x is stored by using the name “ x .”

The type name in the declaration, int , tells the compiler how many bytes to allocate and the code used to represent the data stored at this location. The int type uses the two's complement code. So the assignment statement,

would set the bit pattern in the location named x to \(\hex{0x0000007b}\text{,}\) the two's complement code for the signed integer \(+123\text{.}\) Similarly, the assignment statement

would set the bit pattern in the location named x to \(\hex{0xffffff85}\text{,}\) the two's complement code for the signed integer \(-123\text{.}\)

The program in Listing 11.2.1 uses the assignment operator to store values in the x , y , and z variables. We use the register type modifier to “advise” the compiler to use a register for the x and y variables.

The compiler-generated assembly language shown in Listing 11.2.2 shows the assignment operation implemented in three different ways.

The compiler honored our request to use registers for both the x and y variables, and the z variable is allocated in the stack frame.

Listing 11.2.3 shows my assembly language solution. It is essentially the same as what the compiler generated, but I have used names for labels and constants that will help with the explanation of the code.

First, notice that the values in the r4 and r5 registers must be saved on the stack in the prologue:

and restored in the epilogue:

as is specified in Table 10.1.1 .

After setting up our frame pointer, we move the stack pointer to allocate space on the stack for the local variable:

where the value of local was computed to (a) allow enough memory space for the int variable, and (b) make sure the stack pointer is always on an eight-byte addressing boundary, as required by the protocol when calling a public function ( printf in this case).

You have already seen the first two assignment implementations:

in Listing 10.1.4 . The integer value, \(123\text{,}\) is within the range that can be moved directly into a register. However, \(4567\) cannot, so it is stored in memory and loaded into a register from memory.

The compiler honored our request to use registers for both the x and y variables. However, the z variable is allocated in the stack frame. So after the addition is performed, the sum is stored in memory at a location relative to the frame pointer:

Recall from Section 9.2 that [fp, z] specifies the address obtained by adding the value of z to the value contained in the fp register. In this function z is an offset of \(-16\) bytes from the address in fp .

In Section 11.3 we discuss the machine code for the instructions that implement these assignment statements. In particular, we will be looking at how the location of each variable is encoded in the machine language.

Assignment on Computer Programming Languages

Computer Programming Language

Computer Programming languages were first developed with a series of steps with the vision to wire a desired program.  These morphed into a wide series of particular steps put into the computer to be executed.  later  on with more and more research these languages acquired  some advanced features such as logical branching and object orientation.

What Is PHP?

The World Wide Web has changed very fast in so many ways. Sometimes it seems like yesterday that a little known markup language with a strange name HTML (Hyper Text Markup Language) was used by some physicists to link scientific documents at a group of CERN servers. It was wondrous to read some text somewhere in the world with just a simple program, and what is more information in the document could magically transport you to another one with related information. And this spread relatively quickly to other sciences. Text-only interfaces were the norm, and simplicity of accessing information content the most important part of the equation. Text documents with a small set of tags and a simple server setup was all you needed to inform your colleagues and share the knowledge , independently of whether the organic chemist at the other end was using his trusty Mac, or the theoretician was using her Unix box, or the impoverished graduate was using a second or third hand PC running very flaky TCP/IP software. Nowadays we expect more, much more than this. A modern web site is not just a web server; it also includes a way of storing data and querying (a SQL database perhaps), a way of processing the requests from the user and creating documents with the

appropriate information. Open source products will be your best assurance that your application that works now in the “Super-Turbo Hexium IX” machine of today, will work in the “Nanotech Cube Aleph” of tomorrow (I am exaggerating just a wee bit).

Why use php?

PHP (acronym for: PHP Hypertext Preprocessor), is a server-side embedded scripting language. This means that it works within an HTML document to confer to it the capacity of generating content on demand. You can convert your site into a web application, not just a collection of static pages with information that may not get updated quite so often, which may be alright for a “personal” web site (yes, we all have made such a beast), but not for one that is going to be used for business or for education.

You may be asking “But, why PHP? There are so many other options like ASP, Cold Fusion, Perl, Java, Python, even good old shell/awk/sed scripts?”, and the answer will be: simplicity, an almost natural way of using databases and platform independence. PHP was designed to work on the web, and in this ambit it excels; connecting and querying a database is a simple task that can be handled in 2 or 3 lines of code. The PHP scripting engine is well optimized for the response times needed on web applications, it can even be part of the web server itself improving the throughput even more. If it were only a matter of improving the speed of the scripts, then PHP will be one of many solutions .But there is more to the PHP equation than that. There is the simplicity and robustness of the language and the scripting engine. There is the connectivity to an ever increasing number of database servers, the shorter development cycles and the ease (encouraged by the syntaxes and constructs) of creating modular and reusable components .And did I mention that it is open source? There’s no more waiting until the next release for a feature to be added or a bug to get fixed. Just take the source, make your modifications and there you are, instant customization and complete control. No more guessing at whether a particular function or feature is insecure, the code does not lie. And who knows, maybe your modification gets to be so popular that others may want to use it.

Example of PHP

Echo ”I am Samar”;

The output is I am Samar.

Software Availablity

Yes php is free get from internet. You go to URL:www.php.net then you get software of php. The software name is php-tired.

Working Platforms

And you cannot beat the total price for a development environment using the combination of Linux, Apache, MySQL and PHP, not only cheaper than other more proprietary environments, but also more stable and robust.

PHP also use in winxp,winme,2000.

What is JavaScript

M any of the technologies that make the World Wide Web possible have far exceeded their original visions. It’s the enormous popularity of the Web and the accessibility of the technologies to everyday folks who have intriguing ideas that has led to an unprecedented explosion in turning the World Wide Web from a bland publishing medium into a highly interactive, operating system-agnostic authoring platform. The JavaScript language is a Web-enhancing technology. When employed on the client computer, the language can help turn a static page of content into an engaging, interactive, and intelligent experience. Applications can be as subtle as welcoming a site’s visitor with the greeting “Good morning!”   when it is morning in the client computer’s time zone—even though it is dinnertime where the server is located. Or applications can be much more obvious, such as delivering the content of a slide show in one-page download while JavaScript controls the sequence of hiding, showing, and “flying slide” transitions while navigating through the presentation. Of course, JavaScript is not the only technology that can give life to drab Web content. Therefore, it is important to understand where JavaScript fits within the array of JavaScript standards, tools, and other technologies at your disposal. The alternative technologies described in this chapter are HTML, server programs, plug-ins, and Java applets. In most cases, JavaScript can work side by side with these other technologies, even though the hype around some make them sound like one-stop shopping places for all your interactive needs. That’s rarely the case. Finally, you learn about the origins of JavaScript and what role it plays in today’s advanced Web browsers.

The Software Tools

The best way to learn JavaScript is to type the HTML and scripting code into documents in a text editor. Your choice of editor is up to you, although I provide you with some guidelines for choosing a text editor in the next section.

Choosing a text editor

For the purposes of learning JavaScript in this book, avoid WYSIWYG (What You See Is What You Get) Web page authoring tools, such as FrontPage and  Dream Weaver, for now. These tools certainly will come in handy afterward when you can productively use those facilities for molding the bulk of your content and layout. But the examples in this book focus more on script content (which you must type in anyway), so thereisn’t much HTML that you have to type. Files for all complete Web page listings (except for the tutorial chapters) also appear on the companion CD-ROM.To save the file initially as a text or / extension file requires mucking around in the Save As dialog box. This requirement is truly a nuisance. Nothing’s wrong with using bare-essentials text editors. In Windows, that includes the WordPad program or a more fully featured product such as the shareware editor called TextPad. For the MacOS, Simple Text is also fine—although the lack of a search-and-replace function may get in the way when you start managing your Web site pages. A favorite among Mac HTML authors and scripters is BBEdit (Bare Bones Software), which includes a number of useful aids for scripters, such

as optional line numbers (which help in debugging JavaScript).

Example of javascript

<HTML>

<HEAD>

<TITLE>My First Script</TITLE>

</HEAD>

<BODY>

<H1>Let’s Script…</H1>

<SCRIPT LANGUAGE=”JavaScript”>

<!– hide from old browsers

document.write(“This browser is version “ + navigator.appVersion)

document.write(“ of <B>” + navigator.appName + “</B>.”)

// end script hiding –></SCRIPT></BODY></HTML>

Javascript Software file available in own windows as like Win32 operating systems (Windows 95/98/NT/2000/ME)

Working Platform

I n you set up a productive script-writing and previewing environment on your computer, and then you write a simple script whose results you can see in your JavaScript-compatible browser. Because of differences in the way various personal computing operating systems behave, I present details of environments for two popular variants: Win32 operating systems (Windows 95/98/NT/2000/ME) and the MacOS. For the most part, your JavaScript authoring experience is the same regardless of the operating system platform you use—including Linux or UNIX. Although there may be slight differences in

font designs depending on your browser and operating system,

the information remains the same. Most illustrations of

browser output in this book are made from the Win32 version

of Internet Explorer 5. x .

What Is AJAX?

Understanding AJAX

AJAX is an acronym for Asynchronous JavaScript and XML. If you think it doesn’t say much, we agree. Simply put, AJAX can be reads “empowered JavaScript”, because it essentially offers a technique for client-side JavaScript to make background server calls and retrieve additional data as needed, updating certain portions of the page without causing full page reloads. Figure   offers a visual representation of what happens when a typical   AJAX-enabled web page is requested by a visitor:

                                                 Figure : A Typical AJAX Call

When put in perspective, AJAX is about reaching a better balance between client functionality and server functionality when executing the action requested by the user. Up until now, client-side functionality and server-side functionality were regarded as separate bits of functionality that work one at a time to respond to user’s actions. AJAX comes with the solution to balance the load between the client and the server by allowing them to communicate in the background while the user is working on the page.

 Without AJAX, there were two form validation techniques. The first was to let the user type all the required data, let him or her submit the page, and perform the validation on the server. In this scenario the user experiences a dead time while waiting for the new page to load. The alternative was to do this verification at the client, but this wasn’t always possible (or feasible) because it implied loading too much data on the client (just think if you needed to validate that the entered city and the entered country match).

Description

<html>

<head><title>Ajax foundation: JavaScript and DOM</title>

<script type=”text/javascript” src=”jsdom.js”>

            </script>

</head>

<body>

I love you!

</body>

</html>

This is  Jsdom.js  file

var date=new Date();

var hour=date.getHours();

if (hour >= 22 || hour <= 5)

document.write(“Goodnight world!”);

document.write(“HelloWorld!”);

I present details of environments for two popular variants: Win32 operating systems (Windows 95/98/NT/2000/ME) and the MacOS. For the most part, your AJAX authoring experience is the same regardless of the operating system platform you use—including Linux or UNIX.

What is ASP?

ASP is a server side scripting technology that enables scripts (embedded in web pages) to be executed by an Internet server.

• ASP is a Microsoft Technology
• ASP stands for Active Server Pages
• ASP is a program that runs inside IIS
• IIS stands for Internet Information Services
• IIS comes as a free component with Windows 2000
• IIS is also a part of the Windows NT 4.0 Option Pack
• The Option Pack can be downloaded from Microsoft
• PWS is a smaller – but fully functional – version of IIS
• PWS can be found on your Windows 95/98 CD

What is an ASP File?

• An ASP file is just the same as an HTML file
• An ASP file can contain text, HTML, XML, and scripts
• Scripts in an ASP file are executed on the server
• An ASP file has the file extension “.asp”

How Does it Work?

• When a browser requests an HTML file, the server returns the file
• When a browser requests an ASP file, IIS passes the request to the ASP engine on the server
• The ASP engine reads the file, line by line, and executes the scripts in the file
• Finally, the ASP file is returned to the browser as plain HTML

What is ASP+?

ASP+ is the same as ASP.NET.

ASP+ is just an early name used by Microsoft when they developed ASP.NET.

What is ASP.NET?

ASP 3.0 is the latest version of ASP, but there will never be an ASP 4.0 version.

ASP.NET is the next generation ASP, but it’s not an upgraded version of ASP. ASP.NET is an entirely new paradigm for server-side ASP scripting.

ASP.NET is a part of the .NET Framework. Microsoft spent three years rewriting ASP.NET from the ground up, and ASP.NET is not fully backward compatible with ASP 3.0.

You can read more about the differences between ASP and ASP.NET in the next chapter of this tutorial.

Differences between ASP and ASP .NET

New in ASP .NET

• Better language support
• Programmable controls
• Event-driven programming
• XML-based components
• User authentication, with accounts and roles
• Higher scalability
• Increased performance – Compiled code
• Easier configuration and deployment
• Not fully ASP compatible

Language Support

ASP .NET uses the new ADO .NET.

ASP .NET supports full Visual Basic, not VBScript.

ASP .NET supports C# (C sharp) and C++.

ASP .NET supports JScript as before.

ASP .NET Components

ASP .NET components are heavily based on XML. Like the new AD Rotator, that uses XML to store advertisement information and configuration.

Compiled Code

The first request for an ASP .NET page on the server will compile the ASP .NET code and keep a cached copy in memory. The result of this is greatly increased performance.

Easy Configuration

Configuration of ASP .NET is done with plain text files.

Configuration files can be uploaded or changed while the application is running. No need to restart the server. No more metabase or registry puzzle.

Compatibility

ASP .NET is not fully compatible with earlier versions of ASP, so most of the old ASP code will need some changes to run under ASP .NET.

To overcome this problem, ASP .NET uses a new file extension “.aspx”. This will make ASP .NET applications able to run side by side with standard ASP applications on the same server.

Dynamic Page in Classic ASP

Service Packs and Updates

Before ASP.NET can be installed on your computer, it is necessary to have all relevant service packs and security updates installed.

The easiest way to do this is to activate your Windows Internet Update. When you access the Windows Update page, you will be instructed to install the latest service packs and all critical security updates. For Windows 2000, make sure you install Service Pack 2. I will also recommend that you install Internet Explorer 6.

Read the note about connection speed and download time at the bottom of this page.

Remove Your Beta Version

If you have a Beta version of ASP.NET installed, we recommend that you completely uninstall it. Or even better: start with a fresh Windows 2000 or XP installation.

Install .NET

From your Windows Update you can now select to install the Microsoft .NET Framework.

After download, the .NET framework will install itself on your computer – there are no options to select for installation.

Working  Platforms

A Windows Computer

ASP.NET is a Microsoft technology. To run ASP.NET you need a computer capable of running Windows.

Windows 2000 or XP

If you are serious about developing ASP.NET applications you should install Windows 2000 Professional or Windows XP Professional.

In both cases, make sure you install the Internet Information Services (IIS) from the Add/Remove Windows components dialog.

What is XML?

• XML stands for E x tensible M arkup L anguage
• XML is a markup language much like HTML
• XML was designed to describe data
• XML tags are not predefined. You must define your own tags
• XML uses a Document Type Definition (DTD) or an XML Schema to describe the data
• XML with a DTD or XML Schema is designed to be self-descriptive
• XML is a W3C Recommendation

The Main Difference Between XML and HTML

XML was designed to carry data.

XML is not a replacement for HTML. XML and HTML were designed with different goals:

XML was designed to describe data and to focus on what data is. HTML was designed to display data and to focus on how data looks.

HTML is about displaying information, while XML is about describing information.

Example of XML

The output is:

Hello              my name is Tove,

will be displayed like this:

Hello my name is Tove,

XML is Text-based

XML is a text-based markup language.

One great thing about XML is that XML files can be created and edited using a simple text-editor like Notepad.

However, when you start working with XML, you will soon find that it is better to edit XML documents using a professional XML editor.

Why Not Notepad?

Many web developers use Notepad to edit both HTML and XML documents because Notepad is included with the most common OS and it is simple to use. Personally I often use Notepad for quick editing of simple HTML, CSS, and XML files.

But, if you use Notepad for XML editing, you will soon run into problems.

Notepad does not know that you are writing XML, so it will not be able to assist you.

Why an XML Editor?

Today XML is an important technology, and development projects use XML-based technologies like:

• XML Schema to define XML structures and data types
• XSLT to transform XML data
• SOAP to exchange XML data between applications
• WSDL to describe web services
• RDF to describe web resources
• XPath and XQuery to access XML data
• SMIL to define graphics

To be able to write error-free XML documents, you will need an intelligent XML editor!

XML Editors

Professional XML editors will help you to write error-free XML documents, validate your XML against a DTD or a schema, and force you to stick to a valid XML structure.

An XML editor should be able to:

• Add closing tags to your opening tags automatically
• Force you to write valid XML
• Verify your XML against a DTD
• Verify your XML against a Schema
• Color code your XML syntax

Nearly all major browsers have support for XML and XSLT.

Mozilla Firefox

As of version 1.0.2, Firefox has support for XML and XSLT (and CSS).

Mozilla includes Expat for XML parsing and has support to display XML + CSS. Mozilla also has some support for Namespaces.

Mozilla is available with an XSLT implementation.

As of version 8, Netscape uses the Mozilla engine, and therefore it has the same XML / XSLT support as Mozilla.

Internet Explorer

As of version 6, Internet Explorer supports XML, Namespaces, CSS, XSLT, and XPath.

Assignment on WEB HOSTING AND SITE PROMOTION

Install Windows Server 2003

Explain on Online Deal

Creating and Configuring FTP Server

Report on Advertisement with Tele Bangla Group

Scientists Uncover Intestinal Bacteria that Boost Bee Memory

Training Isolated Kegels Exercise in Stress Urinary Incontinence (Part 2)

Informal Meeting Agenda

Lecture on Feminist Literature

Plane Company to Operate 18,000 Ghost Flights to Keep Landing Slots

Latest post.

Plaggen Soil

Arable Land

Online Professional Education is effective for Complicated Topics

School Suspensions and Exclusions Endanger Vulnerable Students

Biosalinity

Soil Salinity Control

Suggestions or feedback?

MIT News | Massachusetts Institute of Technology

• Machine learning
• Sustainability
• Black holes
• Classes and programs

Departments

• Aeronautics and Astronautics
• Brain and Cognitive Sciences
• Architecture
• Political Science
• Mechanical Engineering

Centers, Labs, & Programs

• Abdul Latif Jameel Poverty Action Lab (J-PAL)
• Picower Institute for Learning and Memory
• Lincoln Laboratory
• School of Architecture + Planning
• School of Engineering
• School of Humanities, Arts, and Social Sciences
• Sloan School of Management
• School of Science
• MIT Schwarzman College of Computing

Reasoning skills of large language models are often overestimated

Press contact :.

Previous image Next image

When it comes to artificial intelligence, appearances can be deceiving. The mystery surrounding the inner workings of large language models (LLMs) stems from their vast size, complex training methods, hard-to-predict behaviors, and elusive interpretability.

MIT's Computer Science and Artificial Intelligence Laboratory (CSAIL) researchers recently peered into the proverbial magnifying glass to examine how LLMs fare with variations of different tasks, revealing intriguing insights into the interplay between memorization and reasoning skills. It turns out that their reasoning abilities are often overestimated.

The study compared “default tasks,” the common tasks a model is trained and tested on, with “counterfactual scenarios,” hypothetical situations deviating from default conditions — which models like GPT-4 and Claude can usually be expected to cope with. The researchers developed some tests outside the models’ comfort zones by tweaking existing tasks instead of creating entirely new ones. They used a variety of datasets and benchmarks specifically tailored to different aspects of the models' capabilities for things like arithmetic, chess, evaluating code, answering logical questions, etc.

When users interact with language models, any arithmetic is usually in base-10, the familiar number base to the models. But observing that they do well on base-10 could give us a false impression of them having strong competency in addition. Logically, if they truly possess good addition skills, you’d expect reliably high performance across all number bases, similar to calculators or computers. Indeed, the research showed that these models are not as robust as many initially think. Their high performance is limited to common task variants and suffer from consistent and severe performance drop in the unfamiliar counterfactual scenarios, indicating a lack of generalizable addition ability.  The pattern held true for many other tasks like musical chord fingering, spatial reasoning, and even chess problems where the starting positions of pieces were slightly altered. While human players are expected to still be able to determine the legality of moves in altered scenarios (given enough time), the models struggled and couldn’t perform better than random guessing, meaning they have limited ability to generalize to unfamiliar situations. And much of their performance on the standard tasks is likely not due to general task abilities, but overfitting to, or directly memorizing from, what they have seen in their training data. “We’ve uncovered a fascinating aspect of large language models: they excel in familiar scenarios, almost like a well-worn path, but struggle when the terrain gets unfamiliar. This insight is crucial as we strive to enhance these models’ adaptability and broaden their application horizons,” says Zhaofeng Wu, an MIT PhD student in electrical engineering and computer science, CSAIL affiliate, and the lead author on a new paper about the research. “As AI is becoming increasingly ubiquitous in our society, it must reliably handle diverse scenarios, whether familiar or not. We hope these insights will one day inform the design of future LLMs with improved robustness.” Despite the insights gained, there are, of course, limitations. The study’s focus on specific tasks and settings didn’t capture the full range of challenges the models could potentially encounter in real-world applications, signaling the need for more diverse testing environments. Future work could involve expanding the range of tasks and counterfactual conditions to uncover more potential weaknesses. This could mean looking at more complex and less common scenarios. The team also wants to improve interpretability by creating methods to better comprehend the rationale behind the models’ decision-making processes. “As language models scale up, understanding their training data becomes increasingly challenging even for open models, let alone proprietary ones,” says Hao Peng, assistant professor at the University of Illinois at Urbana-Champaign. “The community remains puzzled about whether these models genuinely generalize to unseen tasks, or seemingly succeed by memorizing the training data. This paper makes important strides in addressing this question. It constructs a suite of carefully designed counterfactual evaluations, providing fresh insights into the capabilities of state-of-the-art LLMs. It reveals that their ability to solve unseen tasks is perhaps far more limited than anticipated by many. It has the potential to inspire future research towards identifying the failure modes of today’s models and developing better ones.” Additional authors include Najoung Kim, who is a Boston University assistant professor and Google visiting researcher, and seven CSAIL affiliates: MIT electrical engineering and computer science (EECS) PhD students Linlu Qiu, Alexis Ross, Ekin Akyürek SM ’21, and Boyuan Chen; former postdoc and Apple AI/ML researcher Bailin Wang; and EECS assistant professors Jacob Andreas and Yoon Kim. 

The team’s study was supported, in part, by the MIT–IBM Watson AI Lab, the MIT Quest for Intelligence, and the National Science Foundation. The team presented the work at the North American Chapter of the Association for Computational Linguistics (NAACL) last month.

Share this news article on:

Related links.

• Jacob Andreas
• Zhaofeng Wu
• MIT-IBM Watson AI Lab
• Computer Science and Artificial Intelligence Laboratory (CSAIL)
• Department of Electrical Engineering and Computer Science

Related Topics

• Electrical Engineering & Computer Science (eecs)
• Quest for Intelligence
• Computer science and technology
• Artificial intelligence
• National Science Foundation (NSF)

Related Articles

Technique improves the reasoning capabilities of large language models

Natural language boosts LLM performance in coding, planning, and robotics

Using ideas from game theory to improve the reliability of language models

Previous item Next item

More MIT News

License plates of MIT

Read full story →

Startup aims to flush away the problem of icky toilet seats

China-based emissions of three potent climate-warming greenhouse gases spiked in past decade

“The dance between autonomy and affinity creates morality”

Machine learning unlocks secrets to advanced alloys

Math program promotes global community for at-risk Ukrainian high schoolers

• More news on MIT News homepage →

Massachusetts Institute of Technology 77 Massachusetts Avenue, Cambridge, MA, USA

• Map (opens in new window)
• Events (opens in new window)
• People (opens in new window)
• Careers (opens in new window)
• Accessibility
• Social Media Hub
• MIT on Facebook
• MIT on YouTube
• MIT on Instagram

• Summer Racing Northeast
• Champions League
• Motor Sports
• High School
• Shop Northeast
• PBR Northeast
• 3ICE Northeast
• Stubhub Northeast
• Play Golf Northeast

2024 WNBA All-Star Game odds, time, spread: Team USA vs. Team WNBA picks, predictions from proven expert

Sportsline's women's basketball expert calvin wetzel has revealed his picks for caitlin clark and team wnba vs. team usa in the wnba all-star game 2024 on saturday.

The WNBA's best are together in Phoenix and the 2024 WNBA All-Star Game will take on a different format as Team USA takes on Team WNBA on Saturday night. The league will go on a break until Aug. 15 with the Summer Olympics starting on July 26. Indiana teammates Caitlin Clark (700,735 votes) and Aliyah Boston (618,680) finished first and second in fan voting. Rounding out the top five in fan voting were A'Ja Wilson (607,300), Breanna Stewart (424,135) and Angel Reese (381,518).

Tipoff is at 8:30 p.m. ET at Footprint Center in Phoenix. Team USA is the 7-point favorite in the latest Team WNBA vs. Team USA odds, while the over/under for total points is 191.5. Before making any Team USA vs. Team WNBA picks, be sure to see the WNBA predictions from SportsLine's women's basketball expert Calvin Wetzel . 

Since the start of the 2021-22 women's college basketball campaign, Wetzel is an insane 1,384-988 (+371.33 units). Wetzel also predicted 66 of 68 NCAA Women's Tournament teams this year, as well as 62 of 68 teams within one seed line, and correctly picked 13 of 16 second-round games. Anybody following him has seen huge returns. 

Now, he has set his sights on Team USA vs. Team WNBA and just locked in his picks and WNBA predictions. You can visit SportsLine now to see his picks. Here are several WNBA betting lines and trends for Team WNBA vs. Team USA:

• Team WNBA vs. Team USA spread: Team USA -7
• Team WNBA vs. Team USA over/under: 191.5 points
• Team WNBA vs. Team USA money line: Team USA -278, Team WNBA +222
• USA: Team USA are seeking their 8th straight gold medal in Paris
• WNBA: Reese and Clark are the only two first-time All-Stars this season
• Team WNBA vs. Team USA picks: See picks at SportsLine

Why Team USA can cover

Phoenix guard Kahleah Copper  is an effortless ball handler and shot creator. Cooper has been named to her fourth straight All-Star appearance. She's second in the league in scoring (23.3). The 29-year-old leads the WNBA with eight games of 30-plus points.

Guard Sabrina Ionescu is another perimeter force. The Oregon product is sixth in the league in scoring (19.8) and fifth in assists per game (6.1). Ionescu has knocked down the second-most 3-pointers in the WNBA (74). Las Vegas guard Kelsey Plum is one of three Aces players averaging 18-plus points this season ( A'Ja Wilson and Jackie Young ). The Washington product is fourth in the WNBA with three 3-pointers made per game.  See which team to pick here . 

Why Team WNBA can cover

Connecticut's DeWanna Bonner has been a driving force for her club all season. Bonner is able to score from multiple spots on the floor with ease. She's been named to five of the last six All-Star games. The 36-year-old is fifth on the all-time scoring list (7,282) and has nine games with 20-plus points this season. 

Dallas guard Arike Ogunbowale is a confident playmaker on the floor. Ogunbowale owns a quick first step and a reliable mid-range jumper. The four-time All-Star is currently second in the WNBA in points per game (22.3). Reese is making her first trip to the All-Star game. She thrives around the rim and is an exceptional rebounder. The LSU product is second in the league in rebounds (11.9) and third in offensive rebounds (4.7) with 13.5 points per contest.  See which team to pick here .

How to make 2024 WNBA All-Star Game picks 

Wetzel is going Under on the point total, and he has also found a critical x-factor that has him jumping all over one side of the spread.  You can only see his picks and analysis at SportsLine .

Which side covers in the 2024 WNBA All-Star Game? Visit SportsLine to see the best bets for Team WNBA vs. Team USA, all from an expert who is +371.33 units on his women's college basketball picks since 2021 , and find out.

Our Latest WNBA Stories

Caitlin Clark sets All-Star Game rookie assist record

Jack maloney • 1 min read.

Ogunbowale named All-Star Game MVP

All-Star Game: Clark, Reese shine in Team WNBA win

Isabel gonzalez • 1 min read.

Engelbert: WNBA considering 44-game schedule for 2025

WNBA All-Star Game: How to watch, stream, preview

Liberty's Breanna Stewart says hamstring feels 'great'

Share video.

Team USA vs. Team WNBA odds, expert picks

Caitlin Clark at No. 1, Vanloo cracks list

Arike Ogunbowale named All-Star Game MVP

Why Caitlin Clark, Ionescu aren't in 3-Point Contest

Schauffele, not Scheffler, now golf's hottest player

Top Hall of Fame induction moments

• icon/add list icon/arrow
• Button/Menu/Account/Focus icon/arrow
• 编组 4 icon/arrow
• icon_Bottom bar_Account_Normal@2x icon/arrow
• Group 2 icon/arrow
• Variety Show

Meet You at the Blossom

Details | meet you at the blossom, description.