802.11 is the overall name for wireless internet
technology. It is also more commonly known as Wi-fi.
There are several variations. 802.11a was a 5Ghz technology which was rarely used. 802.11b was the first common standard providing 11 Mb/s connections and used the 2.4Ghz band which Bluetooth
and other wireless devices such as baby monitor cameras
's original airport technology was 802.11b. It was superseded by 802.11g (which also supports 802.11b hardware
) which runs up to 54 Mb/s. The range is generally a few hundred feet with the speed decreasing as the distance between devices gets larger. Antennas help significantly.
Normally a link with the internet is connected to an Access Point, where any device in the area can connect. Some access poitns are protected by encryption and passwords, and others have gateways which require a sign-on before they can be used.