This document provides an overview of computer networks, including definitions, common uses, types, topologies, hardware, cabling, and protocols. It defines a network as a set of technologies that connects computers and allows communication between users. Common uses of networks include simultaneous access to shared data files, shared peripheral devices like printers, personal communication via email, and easier data backup when stored on a server. The document discusses different network types including LANs, WANs, MANs, and topologies like star, bus, ring and mesh. It also covers common networking hardware, cabling standards, and protocols such as TCP/IP, IPX/SPX, and NetBEUI.