Local Area Network — Wide Area Network
LAN: Local Area Network
A LAN is limited in size (twisted‑pair cables up to 100 meters / fiber up to 2 km, sometimes more).
The LAN administrator is personally responsible for the network, the cabling, and the equipment.
Both Ethernet and WiFi are LAN technologies.
WAN: Wide Area Network
A WAN is unlimited in size. Point‑to‑point connections are often used.
An external organization (telecom provider or similar) is responsible for these connections in exchange for payment.