This document provides an overview of computer networking theory and practice. It discusses the key components of a computer network including network interface cards, hubs, routers, modems, switches, and cables. It describes different types of networks like local area networks, wide area networks, and wireless networks. The document also covers the uses of computer networks like resource sharing, communication, the server-client model, e-commerce, and as a communication medium. Finally, it discusses the benefits of computer networks such as sharing resources, improved communication, increased security, remote access, and cost savings, as well as some potential disadvantages.