The http Module
Node's built-in http module powers web servers and clients.
Syntax
const http = require('http');The built-in http module lets you build web servers and make HTTP requests — no external library required. It is the foundation that frameworks like Express are built on.
What a server does
A server listens on a port for incoming requests. For each request it receives a request object (what the client wants) and a response object (what you send back).
Example
const http = require('http');
// The simplest possible server
const server = http.createServer((req, res) => {
res.end('Hello, HTTP!');
});
server.listen(3000, () => {
console.log('Listening on http://localhost:3000');
});When to use it
- A microservice team creates a lightweight internal health-check server using only the built-in `http` module to avoid Express overhead.
- A developer learning Node.js builds their first web server without any framework to understand how HTTP works at the protocol level.
- A webhook receiver uses `http.createServer` to listen for POST requests from a third-party payment provider without framework dependencies.
More examples
Minimal HTTP server
The smallest possible HTTP server -- creates, configures, and starts listening in seven lines.
const http = require('http');
const server = http.createServer((req, res) => {
res.writeHead(200, { 'Content-Type': 'text/plain' });
res.end('Hello, HTTP!\n');
});
server.listen(3000, () => console.log('Listening on :3000'));Inspect request method and URL
Logs the HTTP method and URL of every incoming request -- the two most important properties of `req`.
const http = require('http');
http.createServer((req, res) => {
console.log(`${req.method} ${req.url}`);
res.writeHead(200);
res.end();
}).listen(3000);Send custom headers
Sets individual response headers with `setHeader` and a status code with `writeHead` before sending the body.
const http = require('http');
http.createServer((req, res) => {
res.setHeader('X-Powered-By', 'Node.js');
res.setHeader('Cache-Control', 'no-store');
res.writeHead(200, { 'Content-Type': 'application/json' });
res.end(JSON.stringify({ ok: true }));
}).listen(3000);
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