A local area network, or LAN, links computers that are physically close together-in the same building or group of buildings, for example. In a wide area network, or WAN, the computers are farther apart. A personal area network, or PAN, spans an even shorter distance than a LAN, up to 30 feet. It's used both to access a larger network and to enable devices like printers and PDAs in a person's general area to work with one another.