How do computers talk to each other?

Ethernet is a standard protocol that allows any number of computers to communicate with one another. These machines need to be connected to one another through Ethernet cable, or "Category 5" wiring. Similar to a phone line, Ethernet cables can have from four to eight wires, as much as double the amount found in a phone line.

Ethernet cable is usually a bit thicker than a phone line, and the jack looks like an oversized phone plug. Even an inexpensive home network will run at very high speeds, usually 10 or 100 Mbps. That's 200-2,000 times faster than a 56K dial-up connection! You can even configure your network to perform at twice that speed ("full duplex") if you need to stream audio or video across the network. Internet Service Providers (ISPs) may run their networks at 1000 Mbps (a gigabit).

The Ethernet standard is what allows these machines to talk to one another. Each computer (or printer or other device) that is connected to this Ethernet cable is set up to have a unique address, or IP Address.

What's an IP address?