In information technology, a network is a series of points or nodes interconnected by communication paths.

Networks can interconnect with other networks and contain subnetworks. The most common topology or general configurations of networks include the bus, star, token ring, and mesh topologies. Networks can also be characterized in terms of spatial distance as local area networks (LANs), metropolitan area networks (MANs), and wide area networks (WANs). A given network can also be characterized by the type of data transmission technology in use on it (for example, a TCP/IP or Systems Network Architecture network); by whether it carries voice, data, or both kinds of signals; by who can use the network (public or private); by the usual nature of its connections (dial-up or switched, dedicated or nonswitched, or virtual connections); and by the types of physical links (for example, optical fiber, coaxial cable, and Unshielded Twisted Pair). Large telephone networks and networks using their infrastructure (such as the Internet) have sharing and exchange arrangements with other companies so that larger networks are created. To explore how networks are used in the enterprise, here are some additional resources: The essential guide for upgrading your network: This chapter download explores the challenges, best practices and technologies for responding to the shortcomings of today's network, as well as future-proofing for tomorrow's challenges. Network evaluation and roadmap: This chapter download shows you how to perform an impact analysis to evaluate bandwidth and processing needs and develop a roadmap for an architecture that will fulfill your network requirements. Download this free computer networking PDF that introduces network architecture, details the different parts of a computer network, and identifies key metrics to evaluate the performance of computer networks.