The cache contains cached copies of releases and artists downloaded from MusicBrainz and Discogs, and searches from Acoustid.
These are all cached for performance reasons. Emptying the cache does not affect functionality it only affects performance. We may also wish to clear out the cache because would like to force SongKong to retrieve new versions of data from MusicBrainz and Discogs
We can empty the cache by selecting the Empty Cache option from the Admin menu.