The Internet and DNS

The internet is a global network of networks — a vast WAN connecting billions of devices worldwide. This lesson covers the structure of the internet, how data finds its way across it, and the critical role of the Domain Name System (DNS).

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What is the Internet?

The internet is a worldwide collection of interconnected networks. It is not a single network owned by one organisation — it is a network of networks, linked together by routers, fibre optic cables, satellite links and other infrastructure.

Key facts

• The internet began as ARPANET in the late 1960s, a US Department of Defense research project.
• It uses TCP/IP protocols to enable communication between different networks and devices.
• The internet provides the infrastructure for services such as the World Wide Web, email, file transfer and streaming.

Important distinction: The internet is the physical network infrastructure (cables, routers, servers). The World Wide Web (WWW) is a service that runs on top of the internet — it is a collection of web pages accessed through browsers using HTTP/HTTPS.

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How the Internet Works

IP Addresses