A local area network (LAN) is a computer network covering a small geographic area, like a home, office, or group of buildings. The defining characteristics of LANs, in contrast to Wide area networks (WANs), include their much higher data transfer rates, smaller geographic range, and lack of a need for leased telecommunication lines.
Ethernet over twisted pair cabling, and Wi-Fi are the most common two technologies currently, but ARCNET, Token Ring and many others have been used in the past.