802.11g is an extension of the 802.11b wireless network standard from 1999. 802.11g was ratified in 2003. 802.11g works at 2.4GHz and includes speeds up to 54 Mbit using OFDM.
802.11g compliant equipment, such as wireless Access Points, are able to provide simultaneous WLAN connectivity for both 802.11g and 802.11b equipment.
see also 802.11b