The term actually has many different meanings depending on the person, company, or context in which it is being used. Basically, it is a collection of two or more computers and associated devices that are linked together with communications equipment. Once connected, each part of the network can share the software, hardware, and information contained in the other parts.
Also, you may hear Internet companies refer to their "network of Web sites," a group of associated sites that's analogous to a television network or cable TV network.
If you have a small business that uses a network for Internet access and file sharing, be sure to have a firewall installed, to protect yourself from unauthorized access.