The Internet vs. The Web

These two terms are often used interchangeably, but they refer to different things. The internet is the global physical infrastructure — the cables, routers, servers, and wireless signals that connect billions of devices worldwide. The World Wide Web is a service that runs on top of the internet: a system of linked documents and resources accessed via browsers. Email, video calls, and file transfers are also internet services, but they are not "the web."

The Physical Layer: How Devices Connect

At its most basic, the internet is a network of networks. Your home router connects to your Internet Service Provider (ISP) via a physical connection — copper telephone lines, coaxial cable, or fiber-optic cable. Your ISP connects to larger regional networks, which in turn connect to global backbone networks. Intercontinental data travels primarily through submarine fiber-optic cables laid along the ocean floor — thousands of kilometers of glass threads carrying data as pulses of light.

IP Addresses: The Postal System of the Internet

Every device connected to the internet is assigned an IP address (Internet Protocol address) — a unique numerical label that functions like a postal address. Current addresses follow either the older IPv4 format (e.g., 192.168.1.1) or the newer IPv6 format, which provides a vastly larger pool of addresses to accommodate the world's growing number of connected devices.

How Data Travels: Packets and Routing

Data on the internet is not sent as a single continuous stream. Instead, it is broken into small chunks called packets, each typically around 1,500 bytes. Each packet contains:

  • A header with source and destination IP addresses
  • Sequence information so the receiving device can reassemble the data correctly
  • The actual data payload

These packets travel independently across the network, potentially taking different routes, and are reassembled at the destination. This design — developed for resilience during the Cold War — means that if one path is congested or broken, packets simply route around it. Devices called routers make forwarding decisions at each step, reading destination addresses and choosing the best next hop.

The Domain Name System (DNS)

Humans remember names, not numbers. The Domain Name System (DNS) is the internet's phonebook — it translates human-readable domain names like encyclopedie.com into the IP addresses that routers understand. When you type a URL, your device first queries a DNS server to find the corresponding IP address before any data is requested from the destination site. This lookup typically takes milliseconds.

Protocols: The Rules of Communication

For devices made by different manufacturers in different countries to communicate, everyone must follow the same rules. These agreed-upon rules are called protocols. The key ones include:

  • TCP/IP (Transmission Control Protocol / Internet Protocol): The foundational suite governing how packets are addressed and reliably delivered.
  • HTTP/HTTPS (HyperText Transfer Protocol): The protocol for requesting and delivering web pages. HTTPS adds encryption via TLS.
  • SMTP/IMAP: Protocols governing email transmission and retrieval.

What Happens When You Load a Web Page

  1. You type a URL into your browser.
  2. Your device queries a DNS server to resolve the domain to an IP address.
  3. Your browser opens a connection to the web server at that IP address using the TCP protocol.
  4. If HTTPS, a TLS handshake occurs to establish an encrypted connection.
  5. Your browser sends an HTTP GET request for the page.
  6. The server sends back the HTML, CSS, and JavaScript files, broken into packets.
  7. Your browser receives and reassembles these packets and renders the page.

The Cloud and Data Centers

Much of the internet's content and services don't live on personal computers — they reside in data centers, large facilities housing thousands of servers. "The cloud" is simply a marketing term for using computing resources (storage, processing power, software) hosted in these data centers rather than on your own device. Major cloud providers operate data centers strategically around the world to reduce latency and increase reliability.