Summary of Node.js Built-in Modules

Node.js comes equipped with a variety of built-in modules that provide essential functionalities for building applications. Understanding these modules is crucial for effective Node.js development.

Key Concepts

• Modules: In Node.js, a module is a reusable block of code that can be included in other files. Node.js has many built-in modules that simplify common tasks.
• Commonly Used Built-in Modules:
  • HTTP: Used to create web servers and handle HTTP requests and responses.
  • File System (fs): Allows interaction with the file system (read, write, and delete files).
  • Path: Provides utilities for working with file and directory paths.
  • Event Emitter: Enables handling of events and asynchronous programming.
  • Express: Although not a built-in module, it’s a popular framework built on top of Node.js that simplifies server-side development.

Examples of Built-in Modules

File System Module Example:

const fs = require('fs');

fs.readFile('example.txt', 'utf8', (err, data) => {
    if (err) {
        console.error(err);
        return;
    }
    console.log(data);
});

HTTP Module Example:

const http = require('http');

const server = http.createServer((req, res) => {
    res.statusCode = 200;
    res.setHeader('Content-Type', 'text/plain');
    res.end('Hello World\n');
});

server.listen(3000, '127.0.0.1', () => {
    console.log('Server running at http://127.0.0.1:3000/');
});

Conclusion

Node.js built-in modules are powerful tools that help developers perform various tasks without needing third-party libraries. By understanding and utilizing these modules, beginners can build robust applications more efficiently.