Wardriving is the act of searching for Wi-Fi wireless networks by a person in a moving vehicle, using a portable computer or PDA.
[Source: Wikipedia]

Wardriving is driving around a city searching for the existence of Wireless Networks (802.11). It’s locating and logging wireless access points while in motion. Often, this task is automated using dedicated wardriving software and a GPS Device.
[Source: http://www.wardrive.net/]

All said, thats wardriving