Explain various wireless (802.11 family) protocols

IEEE 802.11 also known by the brand Wi-Fi, denotes a set of Wireless LAN. The 802.11 family currently includes six over-the-air modulation techniques that all use the same protocol.
802.11a

Release Date 	Op. Frequency 	Data Rate (Typ) 	Data Rate (Max) 	Range (Indoor)

October 1999 	5 GHz 		25 Mbit/s	 	54 Mbit/s 		~30 meters

	

802.11b

Release Date 	Op. Frequency 	Data Rate (Typ) 	Data Rate (Max) 	Range (Indoor)

October 1999 	2.4 GHz 	6.5 Mbit/s 		11 Mbit/s 		~30 meters

802.11g

Release Date 	Op. Frequency 	Data Rate (Typ) 	Data Rate (Max) 	Range (Indoor)

June 2003 	2.4 GHz 	24 Mbit/s 		54 Mbit/s 		~30 meters

802.11n

Release Date 	Op. Frequency 	Data Rate (Typ) 	Data Rate (Max) 	Range (Indoor)

Unfinished 	2.4(or 5)GHz 	200 Mbit/s 		540 Mbit/s 		~50 meters