HTTP - HyperText Transfer Protocol

HTTP - HyperText Transfer Protocol

What is HTTP?

The protocol used for transmitting web pages across the Internet. When you type a URL in your browser, HTTP defines how your browser requests the page and how the web server responds.

How HTTP Works:

• Request-Response model: Client (browser) sends request, server sends response
• HTTP Request: "GET /index.html" - browser asks server for specific page
• HTTP Response: Server sends HTML, CSS, JavaScript, images
• Stateless: Each request is independent - server doesn't remember previous requests
• Port: Uses port 80 by default

HTTP Methods:

• GET: Request data from server (e.g., load webpage)
• POST: Send data to server (e.g., submit form, login)
• PUT: Update existing data on server
• DELETE: Remove data from server

HTTP Example Flow:

1. You type www.bbc.co.uk in browser
2. Browser sends: GET /index.html HTTP/1.1
3. Server responds: HTTP/1.1 200 OK
4. Server sends HTML page
5. Browser displays webpage

HTTP Limitations:

• NOT secure: Data transmitted in plain text
• Can be intercepted: Anyone on network can read HTTP traffic
• No encryption: Passwords, credit cards sent openly
• Vulnerable: Man-in-the-middle attacks possible