The internet

What is the internet? It is a network of interconnected networks.

Your computer connects to your home router to form a small network. The router connects to your internet service provider’s network, which connects to other providers’ networks. These connections extend across regions and countries. Together, networks of many different sizes, connected in layers, form the internet.

How data travels

Wireless communication, such as Wi-Fi, connects devices over relatively short distances—for example, between your phone and your router. Moving data across regions and countries also relies on wired networks that provide long-distance, reliable connections.

When those connections cross oceans, submarine cables play an important role. Most data traveling between continents crosses these cables. Inside them, optical fibers carry data as rapid pulses of light.

The internet we use every day brings together wireless technologies such as Wi-Fi, devices such as phones and computers, and equipment such as cables and routers.

Exchanging data

The internet’s fundamental purpose is to let distant computers exchange data. Messages, photos, videos, web pages, and AI agent responses are all data moving across the internet.

Web services therefore need reliable ways to exchange that data. The internet and the web have developed various methods and shared rules for doing so.

Exercises

Decide whether each statement is True or False.

1. The internet consists of just one enormous network.
2. Wi-Fi can connect nearby devices, such as a smartphone and a router.
3. Data traveling between continents mostly passes through cables under the sea.