Mobile adhoc networking allows users to exchange information in a wireless
environment without the need for a fixed infrastructure. Each user (or
node), equipped with one or more radios, is free to roam about while communicating
with others. The path between any pair of users can traverse multiple wireless
links and the radios themselves can be heterogeneous, thus enabling an
assortment of different types of links to be part of the same adhoc network. [via]
Interesting stuff and a good read.