Lan (in English lan; in Latin laneus, in German Lahn), is an old unit of field measurement used in Poland. Since the 13th century, its value has varied from one location to another. A greater lan (also Franconian, King's, Old Polish) consisted of 43.2 morgs = 23 to 28 hectares. A lesser lan (Chelmno lan) was 30 morg ˜ 17,955 hectare.

Län (Swedish, ) and lääni (Finnish, ) refer to the administrative divisions used in Sweden and previously in Finland. The provinces of Finland were abolished on January 1, 2010.

A LAN is a local area network, a computer network covering a small local area, such as a home or office.

A local area network (LAN) is a computer network that interconnects computers within a limited area such as a residence, school, laboratory, or office building. A local area network is contrasted in principle to a wide area network (WAN), which covers a larger geographic distance and may involve leased telecommunication circuits, while the media for LANs are locally managed.