The IEEE 802.11 standards are a set that describe wireless LAN communications. The 802.11 frequency bands are currently 2.4, 3.6, and 5 GHz. The standard is primarily developed by the IEEE 802.11 Working Group.
Protocols and Revisions
802.11 (1997 original)
The first version of the 802.11 standard, released in 1997 and now known as 802.11 Legacy, specifies wireless information transfer at speeds of up to either one or two megabits per second (Mbps) in the 2.4 GHz range.
Released in 1999, the 802.11a standard specifies communication in the 5 GHz band at speeds of up to 54 Mbps.
The 802.11b standard has a maximum theoretical data transfer speed of 11 Mbps using the 2.4 GHz band used in the original 802.11 standard.
802.11g also uses the 2.4 GHz band, but at speeds of up to 54 Mbps. 802.11g is the most-used of all 802.11 standards as of June 2009.
IEEE 802.11n supports theoretical speeds of up to 600 Mbps in both the 5 and 2.4 GHz bands. The first 802.11n devices were implemented using Draft 2 of the standard.
IEEE 802.11ac supports speeds of up to 1300Mbps.
Wi-Fi is a trademark owned by the Wi-Fi Alliance to mark certified IEEE 802.11 products. The term "Wi-Fi" is often used as a general noun for wireless networking and communications using the 802.11 standards.