As the name suggests, wireless networks, sometimes called Wi-Fi, allow you to connect to the internet without relying on wires. If your home, office, airport or even local coffee shop has a wireless connection, you can access the network from anywhere that is within the wireless area.
Wireless networks rely on radio waves rather than wires to connect computers to the internet. A transmitter, known as a wireless access point or gateway, is wired into an internet connection. This provides a "hot spot" that transmits the connectivity over radio waves. Hotspots have identifying information, including an item called an SSID, that allows computers to locate them. Computers that have a wireless card and have permission to access the wireless frequency can take advantage of the network connection. Some computers may automatically identify open wireless networks in a given area, while others may require that you locate and manually enter information such as the SSID.
Because wireless networks don't require a wire between a computer and the internet connection, it's possible for attackers who are within range to hijack or intercept an unprotected connection. A practice known as war driving involoves individuals equipped with a computer, wireless card and a GPS device driving through areas in search of wireless networks and identifying the specific coordinates of a network location. This information is then usually posted online.