Glossary

Note: these aren't the definitions you'd find in a book. If that's what you want, then go look in a book. These are they way I would explain the terms to someone. I'd appreciate it if you'd let me know of anything that's misleading or just plain wrong, but I'm not trying to be too strict. Life is tough enough. Sometimes, I may show some sarcasm, though.

Cross-Over

A cross-over cable is an ethernet cable that reverses the "transmit" and "receive" pairs from one end to the other. That is, the transmit pair at one end is wired to the pins for the receive pair at the other end. This lets two Ethernet devices talk to each other directly. Otherwise, each Ethernet device needs to be plugged into a hub. See wiring diagram.

Hub

A hub is a little box about the size of a modem that you can interconnect a bunch of 10baseT ethernet lines with. A 10baseT line runs from each computer to the hub; the hub makes sure all the lines get all the traffic. See Routers and Hubs for more info.

LAN

Local Area Network. It's a bunch of computers in reasonable physical proximity interconnected to each other, usually with 10baseT ethernet and a hub. A WAN is used to connect one LAN to another over a large distance.

Router

A Router can be either a box or some software that you run on a PC (Macs included, of course.) Routers are used as traffic directors between two networks, like between your local LAN and your ISP. For more details, see Routers and Hubs.