A wide variety of systems of interconnected components are called networks.
http://en.wikipedia.org/wiki/Network
A computer network is a system for communication among two or more computers.
Computer networks may be categorized with respect to range:
- personal area network (PAN)
- wireless PAN (WPAN)
- local area network (LAN)
- wireless LAN (WLAN) - metropolitan area network (MAN) - wide area network (WAN) -(Tiny area network (TAN)