A computer network is a number of computers linked together to allow them to share resources. Networked computers can share hardwarehardware: The physical components of a computer., softwaresoftware: A general term used to describe an application or a program. and data [data: information without context, eg a list of students with numbers beside their names is data, when it's made clear that those numbers represent their placing in a 100 metre race, the data becomes information ].

Most computer networks have at least one server. A server is a powerful computer that provides one or more services to a network and its users. For example, file storage and emailemail: electronic mail - a message written or typed on a computer and sent electronically rather than by post.