Unknown Artist can mean a number of things. Here are eight possible causes: 1. Your tags are not correct, please fix them! 2. You are listening to track 19 on the Kill Rock Stars label compilation "Kill Rock Stars". (KRS201, 1991) Even the label's website doesn't identify this track. 3.You are listening to an alias of German Funk band The Poets Of Rhythm, who released albums in the guise of compilations of tracks by various artists when, in fact, all tracks were by The Poets Of Rhythm using various aliases. 4. You are listening to The Unknown Artist, a minimal techno producer. 5. You are listening to a CD, not too old to be recognized, and Last.fm simply will not recognize it. 6. You are listening to Cambodian Cassette Archives: http://www.discogs.com/release/563732 7. You are listening to an unidentified CD (possibly burnt) 8. You are listening to a rare recording where there may be limited copies. No data has been archived yet on the internet. User-contributed text is available under the Creative Commons By-SA License and may also be available under the GNU FDL.