Definitions - LAN / WAN
LAN - Local Area Network. A network that interconnects PCs, terminals, workstations, servers, printers, and other peripherals at high speed over short distances (Ethernet, token ring, FDDI, ATM, wireless)
WAN - Wide Area Network. A network that covers long-haul areas and usually utilizes public phone companies (T1/T3, ISDN, xDSL, Frame Relay, SMDS, ATM)