1 In communications, a rather loosely defined term applied to a system that consists of terminals, nodes, and interconnection media that can include lines or trunks, satellites, microwave, medium- and long-wave radio, etc. In general, a network is a collection of resources used to establish and switch communication paths between its terminals. A given network may be classified as a local area network, a metropolitan area network, or a wide area network, the differences lying as much in their style of organization as in their technology or geographical or physical size. Networks and servers have now largely replaced centralized mainframe computers in most applications. See also network architecture, packet switching, message switching, network delay.
2 In electronic circuitry, an interconnection of various electrical elements. A passive network contains no active (amplifying or switching) elements such as transistors; a linear network is a passive network that contains no nonlinear elements such as diodes.
3 (net) In mathematics, a connected directed graph that contains no cycles. Interconnections involving objects such as telephones, logic gates, or computers could be represented using a connected but not necessarily directed graph.