HTTP and HTTPS

Communication between clients and servers happens through a protocol called HTTP.

Understanding HTTP is essential because every web request you make uses it.

What is HTTP?

HTTP stands for HyperText Transfer Protocol.

It is a set of rules that define how data is sent between a client and a server.

When you visit a website, your browser sends an HTTP request, and the server responds with an HTTP response.

How HTTP Works

HTTP follows the request–response model:

• The client sends a request
• The server processes the request
• The server sends back a response

This happens every time you load a page, submit a form, or fetch data from an API.

Structure of an HTTP Request

An HTTP request typically includes:

• Method (GET, POST, etc.)
• URL or path
• Headers (metadata about the request)
• Body (optional data sent to the server)

Structure of an HTTP Response

An HTTP response includes:

• Status code (e.g., 200, 404)
• Headers (metadata about the response)
• Body (the actual content)

What is HTTPS?

HTTPS stands for HyperText Transfer Protocol Secure.

It is the secure version of HTTP.

The key difference is:

• HTTP → data is sent in plain text
• HTTPS → data is encrypted

Why HTTPS Matters

HTTPS protects data as it travels between the client and server.

This is important for:

• Login forms
• Payments
• Personal data
• API requests

Without HTTPS, data can be intercepted.

Key Idea

HTTP defines how communication happens.

HTTPS makes that communication secure.

Modern web applications always use HTTPS.

Summary

• HTTP is the protocol used for web communication
• It follows a request–response model
• Requests and responses have structured formats
• HTTPS encrypts data for security

In the next lesson, you’ll explore the request–response cycle in more detail.