There are so many different types of computer networks in existence; it can be hard to understand the differences between them, particularly the ones with very similar-sounding names. This lesson explains the structures and functions of some of the most popular computer networks. Types of Networks There are several different types of computer networks. Computer networks can be characterized by their size as well as their purpose. The size of a network can be expressed by the geographic area they occupy and the number of computers that are part of the network. Networks can cover anything from a handful of devices within a single room to millions of devices spread across the entire globe. Some of the different networks based on size are: Personal area network, or PAN Local area network, or LAN Metropolitan area network, or MAN Wide area network, or WAN In terms of purpose, many networks can be considered general purpose, which means they are used f...