What is the Internet?

The Internet can be described as a global collection of networked computers. This collection is constantly growing in size as more and more computers are linked to it. This growth occurs when a new client computer is linked to a regional network, either through a local Internet Service Provider (ISP) or by joining a local area network (LAN) that is linked to the regional network. Regional networks are linked together by a global Internet 'backbone' network. Access to this global backbone allows users to access web servers across the world. The whole set of interconnections from the home or office to the global network is the Internet.
Several web sites exist where you can see a map of the Internet backbone. 

How does this vast collection of computers communicate with each other?

This relies on a set of Internationally recognized standards or Protocols that have evolved and been developed over the years. These protocols determine how computers send and receive information. The main protocol that is used on the Internet was invented in the late 1960s and is known as the TCP/IP (Transmission Control Protocol and the Internet Protocol). It is actually a suite of protocols, all ensuring that information can be passed between computers over the Internet. This protocol became the standard for the Internet in 1983.

How is information stored and retrieved on the Internet?

The Internet runs on the client / server model for networked computers. This means that a main or 'server' computer holds information in the form of web sites. The user extracts this information from this server, using a web browser and a desk top or 'client' computer. There are many millions of server computers now linked to the Internet that can be accessed through desktop computers with an Internet connection.