What Is “Require” In Javascript and Nodejs?

JavaScript and Node.js are powerful tools for building web applications and server-side applications. When working with these technologies, you may come across the term “require”. But what exactly is “require” in JavaScript and Node.js?

In JavaScript, “require” is a function that is used to import modules. Modules are reusable pieces of code that can be used to add functionality to your application. By using “require”, you can include these modules in your code and use their functions, variables, or classes.

In Node.js, “require” is a built-in function that allows you to load modules. Node.js uses a module system called CommonJS, and “require” is the primary way to import modules in Node.js. When you use “require” in Node.js, it searches for the specified module in the node_modules folder or in the core Node.js modules.

Here’s an example of how to use “require” in JavaScript:

const math = require('math');

console.log(math.add(2, 3)); // Output: 5

In this example, we are importing the math module using the “require” function. The math module contains a function called add, which we can use to add two numbers together.

Now, let’s see how to use “require” in Node.js:

const http = require('http');

const server = http.createServer((req, res) => {
  res.end('Hello, World!');
});

server.listen(3000);

In this example, we are importing the core Node.js module http using the “require” function. We then use the http.createServer function to create a simple HTTP server that responds with “Hello, World!” to any incoming request.

As you can see, “require” is a powerful feature in JavaScript and Node.js that allows you to easily import and use modules in your code. Whether you’re building a web application or a server-side application, understanding how to use “require” is essential for leveraging the full potential of JavaScript and Node.js.