Earlier JS could only be used for websites/web-apps until Node.js changed that. Node.js is a runtime that allows you to run JavaScript code outside of a web browser. Built on the V8 engine, Node.js is designed for building scalable network apps.
It uses an asynchronous, event-driven, non-blocking I/O model, which makes it lightweight and efficient. This is especially useful for real-time applications like chat servers, APIs, and streaming services. Node.js also comes with npm (Node Package Manager), which provides thousands of libraries and tools for developers to enhance their applications.
Native Modules
Native Node modules, also known as core modules, are built into Node.js. They provide essential functionalities without requiring any additional installation. These modules are written in JavaScript or C++. Some common ones are listed below -
- fs (File System): • Used for file operations like reading, writing, and manipulating the file system.
- http and https
- path • Utilities for working with file and directory paths
- os • Provides operating system-related utility methods and properties
- events • Implements the EventEmitter class, used for handling events and asynchronous functions.
const fs = require('fs');
const http = require('http');
const path = require('path');
// os usage
const os = require('os');
console.log(os.platform());
// event usage
const EventEmitter = require('events');
const myEmitter = new EventEmitter();
myEmitter.on('event', () => {
console.log('An event occurred!');
});
myEmitter.emit('event');For simplifying our experience with Node, we will learn building backend/server using Express.js framework. Express is started from Intro to Express js. To review how basic node and npm packages work for beginners in setting up projects, look at Setting Up Projects Using Node and npm for Beginners.