Networks can have tens, thousands, or even millions of nodes. 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.
Ethernet is relatively inexpensive, easy to set up and use, and very, very fast.
Ethernet networks are categorized by how fast they can move information. There are currently two Ethernet speed categories. Standard Ethernet operates at a fast 10Mbps, which is quick enough for most networking tasks. Fast Ethernet, by contrast, races along at a blistering 100Mbps, making it ideal for desktop video, multimedia, and other speed-hungry applications. The new technology behind Fast Ethernet, which was introduced in the beginning of 1995, is not readily compatible with standard Ethernet.