A network is a group of computers, printers, and other devices that are connected together with cables. Each computer, printer, or other peripheral device that is connected to the network is called a node.
Networks can have tens, thousands, or even millions of nodes.
The most common topologies or general configurations of networks include the bus, star, and ring topologies. Like most things, networks are are assembled according to certain rules. Cabling, for example, has to be a certain length, each cabling strand can only support a certain amount of network traffic, etc. The rules that govern how a network is set up is called its topology. The most popular topology in use today is called Ethernet, which consists of computers and peripherals cabled together in specific ways.