The CDA - CD Audio Track Shortcut extension, is used to locate tracks on audio CDs. The CDA file itself does not contain the audio data, just the location shortcut information. To work properly, the CD must be in the CD drive. CDA files can be found on MACs, PCs and Linux systems. Applications such as iTunes, RealNetwork RealPlayer, VideoLAN VLC media player and Windows Media Player can use CDA files.