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How do you create a simple HTTP server using Node.js?

You can create a simple HTTP server in Node.js using the built-in http module — no external libraries required. Here's a minimal example:

✅ Step-by-Step: Create a Simple HTTP Server

// 1. Import the http module
const http = require('http');

// 2. Define the server logic
const server = http.createServer((req, res) => {
  res.statusCode = 200; // HTTP OK
  res.setHeader('Content-Type', 'text/plain');
  res.end('Hello, world!\n'); // Response body
});

// 3. Start listening on a port
const PORT = 3000;
server.listen(PORT, () => {
  console.log(`Server running at http://localhost:${PORT}/`);
});

🔍 How It Works:

  • http.createServer() creates an HTTP server and defines how it handles requests (req) and responses (res).

  • res.end() sends the response to the client.

  • server.listen() starts the server on a specific port (e.g., 3000).

✅ To Run the Server:

  1. Save the code as server.js

  2. Run in your terminal:

    node server.js

  3. Visit http://localhost:3000 in your browser — you’ll see "Hello, world!"

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