Learn EXPRESS-JS with Real Code Examples

Install Node.js 16+

Initialize project with `npm init`

Install Express via `npm install express`

Create main server file (e.g., `index.js` or `app.js`)

Run server with `node index.js` or `nodemon` for development

Install Node.js 16+

Initialize project with npm

Install Express and dependencies

Configure development tools (nodemon, ESLint)

Verify server runs on localhost

package.json - project dependencies

app.js / index.js - main server file

routes/ - route modules

middleware/ - custom middleware

.env - environment variables

npm init -> initialize project

npm install express -> install Express

node app.js -> run server

nodemon app.js -> run server with auto-reload

npm install --save-dev typescript -> add TypeScript support

Use i18n middleware for localized responses

Supports Unicode and UTF-8

Can serve different locales per request

Integrates with translation libraries

Used globally in multi-language apps

Framework-agnostic for clients

Accessible via any HTTP client

Supports CORS for cross-domain access

Middleware can enforce security and headers

Works on all Node.js-supported platforms

Not handled - Express is backend framework

Serve static HTML/CSS/JS files

Use template engines for dynamic pages

Integrate with frontend frameworks (React/Vue/Angular)

API responses typically in JSON

Stateless per HTTP request by default

Session management via express-session or JWT

Use middleware to maintain context

Database for persistent state

Cache using Redis or memory stores

Parse JSON, URL-encoded, or multipart requests

Connect to SQL/NoSQL databases

Validate inputs using middleware

Cache frequently used data

Log request/response for auditing