IEEE 802.11 introduced the original 2.4 GHz Wi-Fi technology in 1997. The standard defined wireless local-area networking methods, including radio communication in the 2.4 GHz band, but its initial data rates were modest by modern standards.
The first 802.11 specification supported data rates of 1 or 2 megabits per second and included infrared and radio-frequency physical layers. It was followed by amendments that improved performance and helped establish the Wi-Fi market, notably 802.11b in 1999.
The number 802.11 is often used as if it means one fixed technology, but it actually identifies a large family of IEEE amendments. Later versions introduced technologies such as OFDM, multiple antennas, wider channels, and operation in additional frequency bands. Wi-Fi branding groups these generations for consumers, while the IEEE designations identify the technical standards.