The Internet Is Not the Web
The Internet is a global network of interconnected computer networks — the physical infrastructure of routers, cables, fiber optics, and communication protocols that allow computers to talk to each other. It has existed since the late 1960s (ARPANET).
The Web (World Wide Web) is just one application that runs on top of the Internet. Tim Berners-Lee invented it in 1989 by combining three technologies: HTTP (the protocol), HTML (the content), and URLs (the addresses).
Other Internet Applications
The Web is the most visible application on the Internet, but it's far from the only one:
| Application | Protocol | Purpose |
|---|---|---|
| SMTP / IMAP / POP3 | Sending and receiving messages | |
| File Transfer | FTP / SFTP | Moving files between machines |
| Remote Shell | SSH | Secure command-line access to servers |
| Domain Resolution | DNS | Translating domain names to IP addresses |
| Streaming | RTSP / HLS | Audio/video delivery |
Visualizing the Relationship
The Web sits at the application layer, alongside other Internet applications:
┌─────────────────────────────────────────────────────────────────┐ │ Applications (Layer 7) │ │ │ │ ┌─────────┐ ┌──────┐ ┌─────┐ ┌─────┐ ┌──────────────┐ │ │ │ Web │ │ Email│ │ FTP │ │ SSH │ │ DNS / VoIP │ │ │ │ (HTTP) │ │(SMTP)│ │ │ │ │ │ and more │ │ │ └─────────┘ └──────┘ └─────┘ └─────┘ └──────────────┘ │ ├─────────────────────────────────────────────────────────────────┤ │ │ │ The Internet (Infrastructure) │ │ Routers, cables, fiber, wireless, satellites │ │ │ └─────────────────────────────────────────────────────────────────┘