Definition: WAN stands for Wide Area Network. As its name suggests, it is a computer network that covers a far wider area than a LAN (Local Area Network). WANs cover cities, countries, continents and the whole world.
A WAN is formed by linking LANs together. For example, several major LANs in a city can connect together forming a WAN.
When networks connect to form a bigger network (a bigger WAN), the resulting network is called an internetwork, which is generically abbreviated to ‘an internet’. Now when all WANs in the world connect forming a global internet, we call it The Internet, which everyone knows! That’s why the Internet is always written with a capital I. It is the biggest WAN we have.
