LAN and WAN
While the Internet was evolving and creating a way for
organizations to connect to each other and the world,
another revolution was taking place inside organizations.
The proliferation of personal computers inside
organizations led to the need to share resources such as
printers, scanners, and data. Organizations solved this
problem through the creation of local area networks
(LANs), which allowed computers to connect to each other
and to peripherals. These same networks also allowed
personal computers to hook up to legacy mainframe
computers.
An LAN is (by definition) a local network, usually
operating in the same building or on the same campus.
When an organization needed to provide a network over a
wider area (with locations in different cities or states, for
example), they would build a wide area network (WAN).