A computer network is a collection of computers that share resources shared by network nodes. The computers use common communication protocols through digital connections to communicate with one another. Telecommunication network technologies based on physically wired, optical, and wireless radio-frequency systems that can be assembled in a number of network topologies make up these interconnections.

Personal computers, servers, networking hardware, and other specialized or general-purpose hosts can all be nodes in a computer network. Network addresses and hostnames may be used to identify them. Hostnames serve as easy-to-remember labels for nodes, and they're rarely modified after they're assigned. Communication protocols such as the Internet Protocol use network addresses to locate and identify nodes.

The transmission medium used to convey signals, bandwidth, communications protocols to organize network traffic, network size, topology, traffic control mechanism, and organizational goal are all factors that can be used to classify computer networks.

Access to the World Wide Web, digital video, digital music, shared usage of application and storage servers, printers, and fax machines, and use of email and instant messaging programs are all supported via computer networks.

Because it relies on the theoretical and practical application of related fields, computer networking might be regarded as a branch of computer science, computer engineering, and telecommunications. A variety of technological advancements and historical events influenced computer networking.

A computer network uses multiple technologies such as email, instant messaging, online chat, audio, and video telephone conversations, and video conferencing to extend interpersonal connections via electronic means. A network allows network and computing resources to be shared. Users can access and use network resources such as printing a document on a shared network printer or accessing and using a shared storage drive. A network allows authorized users to access information stored on other computers on the network by transferring files, data, and other sorts of information. To complete tasks, distributed computing makes advantage of computing resources spread over a network.

The organizations that own the networks are usually in charge of managing them. Intranets and extranets may be used in private company networks. They may also provide network access to the Internet, which is a global network with no single owner and essentially unlimited connectivity.