What is Express? — Express.js

ANALOGY

Node's http module is a hammer, Express is a full toolbox. With vanilla Node.js you can handle HTTP requests, but you're writing everything from scratch: parsing request bodies, matching URL patterns, setting content-type headers. Express wraps all that into a clean, familiar API. You still control everything — you just don't write the boilerplate.

What Express adds over raw Node.js

—Routing — app.get('/users', handler) instead of manual URL string matching
—Middleware — a composable pipeline for request processing
—Request helpers — req.params, req.query, req.body already parsed
—Response helpers — res.json(), res.status(), res.redirect()
—Error handling — a unified mechanism for catching and responding to errors

Create your first Express project

bash

mkdir my-api && cd my-api
npm init -y
npm install express
npm install --save-dev nodemon  # auto-restart on file changes

# package.json scripts
"scripts": {
  "start": "node src/index.js",
  "dev":   "nodemon src/index.js"
}