A computer network, often simply referred to as a network, is a collection of computers
and devices interconnected by communications channels that facilitate
communications and allows sharing of resources and information among
interconnected devices. Computer networking or Data communications (Datacom) is the engineering discipline concerned with the computer networks. Computer networking is sometimes considered a sub-discipline of electrical engineering, telecommunications, computer science, information technology and/or computer engineering since it relies heavily upon the theoretical and practical application of these scientific and engineering disciplines.
Networks may be classified according to a wide variety of characteristics such as medium used to transport the data, communications protocol used, scale, topology, organizational scope, etc.
A communications protocol defines the formats and rules for exchanging information via a network. Well-known communications protocols are Ethernet, which is a family of protocols used in LANs, the Internet Protocol Suite, which is used not only in the eponymous Internet, but today nearly ubiquitously in any computer network.