A local area network (LAN) is group of interconnected computers and devices (such as printers) that can share information across a relatively limited area. A small LAN might only cover one room or building, while a large LAN might span multiple buildings and incorporate one or more VLANs.

While a LAN can be limited by distance or the number of devices it can interconnect, LANs typically have faster data transfer rates than a WAN.

In a PACS, the presence of a LAN is presumed.