(Complimentary Code Keying/Orthogonal FDM) A hybrid spread spectrum coding method that transmits the header in a single radio frequency (CCK) and the payload in multiple frequencies (OFDM). CCK/OFDM is an option in the 802.11g wireless LAN standard that is designed to avoid collisions with 802.11b (CCK) systems. Since both header (CCK) and payload (OFDM) transmit in the 2.4 GHz range, the CCK header alerts the 802.11b node of a pending transmission. See 802.11, CCK and OFDM.