The WaveCache.wfm file stores all of the waveform display data for the session. If you delete the WaveCache.wfm file, Pro Tools creates a new one the next time you open the session.By storing waveform data in the WaveCache file, sessions open more quickly. The session WaveCache file can be included whenever a session is transferred to another Pro Tools system (7.x and higher).Pro Tools also maintains a distinct WaveCache file inside the Databases folder, which retains waveform data for all files used on the system.Deleting or trashing a WaveCache file does not harm the session or your system. However, the session will take longer to open because it has to recalculate waveform data for any associated audio files and store that data in a new WaveCache file.