Short for wide area network, a WAN is a collection of computers and devices connected by a communications network over a wide geographic area. Wide area networks are commonly connected either through the Internet or special arrangements made with phone companies or other service providers.
When dealing with only wireless devices, a WWAN or Wireless WAN is a wireless network over a larger area that utilizes multiple wireless technologies (e.g., 2G, 3G, 4G, LTE (Long-Term Evolution), and 5G). A WWAN is different than a WLAN (wireless local area network) in that it covers a much larger area (e.g., a city) and uses more than only Wi-Fi, which can only cover small distances.
MAN, LAN, and WAN
A WAN is different from a MAN (metropolitan area network) because of the distance between each of the networks. In a WAN, one network may be anywhere from several hundred miles away, to across the globe in a different country. The same difference applies to a LAN (local area network). Computers in a LAN are usually close to each other, but a WAN can have larger distances between computers and networks in the WAN.
WAN on a home router
On home routers, the port your home network uses to connect to the Internet is labeled as WAN, Network, or Internet. The picture below is an example of the Internet port on the back of a home router, next to four standard Ethernet ports. In this example, if your broadband uses a modem, it connects to the router's WAN (Internet) port, and computers connect to the other available Ethernet ports.
What is the largest WAN in the world?
The Internet is a collection of networks and is considered the largest WAN in the world.