JavaScript // Runtime

NODE.JS

Node.js takes JavaScript out of the browser and puts it on the server. Built on Chrome's V8 engine, it uses an event-driven, non-blocking I/O model that makes it lightweight and efficient for data-intensive real-time applications.

The V8 Engine

Node.js isn't a language; it's a Runtime. It wraps Google's V8 engine (written in C++) to compile JS into native machine code, giving it incredible performance for a scripting language.

Non-Blocking I/O

Handles thousands of concurrent connections without creating new threads.

NPM

The largest software registry in the world. 1.3M+ packages.

Microservices

Build small, independent services that communicate via APIs.

File System

Read and write files directly to the server's hard drive.

The Full Stack

With Node, you can use the same language (JS) for the Frontend, Backend, and Database (MongoDB). This is the MERN stack.

server.js

const express = require('express');

const app = express();

// Define Route

app.get('/api/users', (req, res) => {

// Simulating DB Call

const users = db.findAll();

res.json(users);

});

app.listen(3000);

Server listening on port 3000...

Client (Browser / Postman)

GEThttp://localhost:3000/api/users

No Data Fetched

Key Frameworks

Express

Minimalist web framework for servers.

npm install express

Socket.io

Real-time, bidirectional communication.

npm install socket.io

Mongoose

Object modeling for MongoDB.

npm install mongoose