Question

what is the purpose of LAN

Answer 1

"Local area network(LAN) is a computer network that spans a relatively small area. Most often, aLAN is confined to a single room, building or group of buildings, however, one LAN can be connected to other LANsover any distance via telephone lines and radio waves."

Answer 2

Main purposes:

File sharingPrinters, scanners, …etc sharingLocal servers for backups, centralized management, …etc