Welcome to Node.js!

Node.js is a JavaScript runtime built on Chrome's V8 engine that lets you run JavaScript on the server.

Why Node.js?

• Fast: Non-blocking, event-driven architecture
• JavaScript Everywhere: Same language for frontend and backend
• NPM: Largest ecosystem of libraries
• Scalable: Perfect for real-time applications

Your First Node.js Program:

// app.js
console.log("Hello from Node.js!")

Run it with: node app.js

Built-in Modules:

Node.js comes with many built-in modules:

const os = require('os')
console.log('Platform:', os.platform())
console.log('CPU cores:', os.cpus().length)

Creating a Simple Server:

const http = require('http')

const server = http.createServer((req, res) => {
  res.writeHead(200, { 'Content-Type': 'text/plain' })
  res.end('Hello World!')
})

server.listen(3000, () => {
  console.log('Server running on port 3000')
})

Task: Create your first Node.js program.