What is HTTP?
HTTP (HyperText Transfer Protocol) is the basic protocol used for communication between a client (browser) and a server on the web.
- Data is sent in plain text
- Anyone who intercepts the traffic can read or modify it
- Commonly used on port 80
Example
- If you submit a login form over HTTP:
- Username and password travel unencrypted
- Attackers on the same network (public Wi-Fi) can sniff the data
What is HTTPS?
HTTPS (HyperText Transfer Protocol Secure) is the secure version of HTTP.
- Uses SSL/TLS encryption
- Data is encrypted, authenticated, and integrity-protected
- Commonly used on port 443
HTTPS = HTTP + TLS (Transport Layer Security)
Key Differences Between HTTP and HTTPS
| Feature | HTTP | HTTPS |
|---|---|---|
| Encryption | No | Yes (TLS/SSL) |
| Data safety | Can be intercepted | Protected |
| Authentication | None | Server identity verified |
| Data integrity | Can be altered | Cannot be tampered |
| Port | 80 | 443 |
| SEO | Lower priority | Preferred by Google |
| Browser warning | No warning | “Not Secure” if missing |
How HTTPS Works (High Level)
- Browser requests a secure connection
- Server sends SSL/TLS certificate
- Browser verifies certificate with a trusted Certificate Authority (CA)
- A secure encrypted session is established
- All data exchanged is encrypted
Why HTTPS Is Important
- Protects login credentials
- Secures payments & personal data
- Prevents man-in-the-middle (MITM) attacks
- Required for:
- Modern browsers
- SEO ranking
- PWA, Service Workers
- HTTP/2 and HTTP/3
Real-World Example
HTTP
http://example.com/login
Password: admin123 → visible in network traffic
HTTPS
https://example.com/login
Password → encrypted (unreadable to attackers)
Do You Always Need HTTPS?
Yes, in modern web applications.
Even for:
- Blogs
- Admin panels
- APIs
- Internal tools
Free SSL certificates are available (e.g., Let’s Encrypt).
Short Summary
- HTTP → fast but insecure
- HTTPS → fast, secure, and trusted
- Today, HTTPS is the standard, not optional
