Wide area network(WAN) - It is a set of connecting links between local area networks (LAN). These links are made over telecommunication lines lease from the various telephone companies. WANs can be created with satellite links, packet radio, or microware transceivers. These options are generally more expensive than leased telephone lines, but they can operates in areas where lease lines are not available.

Most WANs are private and owned by the business that operates with them. Today, the internet has emerged as both the largest and the least expensive WAN in the world.Many copmanies are now forming private WANs, knowns as Virtual Private Networks (VPNs).