Initially PCs had only the most rudimentary abilities to connect to other computers. It quickly became clear that different PCs in an office should be connected, mainly to share files and printers. PC LANs were typically installed with LAN-based email.
PC LANs (local area networks) started to appear in about 1980. Early vendors were Nestar and 3Com. Novell launched its Netware network operating system in 1983, and this enjoyed great success as the main method of connecting office PCs until about 2000. Mass adoption of PC LANs began from about 1986.–David Ferris