802.11 refers to a family of specifications developed by the IEEE for wireless LAN technology. 802.11 specifies an over-the-air interface between a wireless client and a base station or between two wireless clients.

Like many standards, 802.11 has gone through many iterations and expansions over the years. Initially encompassing a 1 Mbps throughput on a 900 MHz channel, it now supports up to 54 Mbps in the 2400 MHz and 5600 MHz bands.

Internationally, there are 14 standard channels, which are spaced at 5 MHz intervals, from 2.4000 to 2.487 GHz. Only channels 1 through 11 are legal in the U.S.A. The 802.11 channel is 22 MHz wide, so it occupies multiple 5 MHz channels. Only channels 1, 6, and 11 can be assigned to an 802.11 network with no overlap among them. If closer spaced channels are assigned, there will be inter-carrier interference generated. Such overlapping systems can still work, but the interchannel interference will effectively raise the noise floor in the channel, which will have a negative impact on the throughput and range of the systems.