What is the difference between IEEE 802.11n IEEE 802.11g IEEE 802.11b?

IEEE 802.11, 1997, the original standard (2Mbit/s, working at bai2.4GHz).
IEEE 802.11a, 1999, physical layer supplement (dao54Mbit/s, working at 5GHz).
IEEE 802.11b, 1999, physical layer supplement (11Mbit/s working at 2.4GHz).
IEEE 802.11c, in line with 802.1D MAC Layer Bridging (MAC Layer Bridging).
IEEE 802.11d, adjusted according to national radio regulations.
IEEE 802.11e, support for Quality of Service (QoS).
IEEE 802.11f, Inter-Access Point Protocol (IAPP, Inter-Access Point Protocol), was approved and revoked by IEEE in February 2006.
IEEE 802.11g, 2003, physical layer supplement (54Mbit/s, working at 2.4GHz).
IEEE 802.11h, 2004, adjustment of wireless coverage radius, indoor (indoor) and outdoor (outdoor) channels (5GHz frequency band).
IEEE 802.11i, 2004, a supplement to the security aspects of wireless networks.
IEEE 802.11j, 2004, an upgrade based on Japanese regulations.
IEEE 802.11l, reserved and ready to not be used.
IEEE 802.11m, maintenance standard; mutual exclusion and limit.
IEEE 802.11n, draft, improvement of higher transmission rate, support for Multi-Input Multi-Output (MIMO) technology.
IEEE 802.11k, the protocol specification stipulates the wireless local area network spectrum measurement specification. The formulation of this specification reflects the demand for the intelligent use of spectrum resources by wireless local area networks.
IEEE 802.11p, this communication protocol is mainly used in the wireless communication of automotive electronics. It is set to expand and extend from IEEE 802.11 to meet the related applications of Intelligent Transportation Systems (ITS)