A Cover Version of a song is a song that is recorded by a different artist than the original.
Cover versions are mostly used in Guitar Hero because of an artist not allowing the use of the original Master Track or otherwise not having the master track available. Cover versions are shown by the song as made famous by such as Heart-Shaped Boxas made famous byNirvana.
A Master Track is the original recording of a song by an artist. All songs on CD, record, cassette, or any other form of media are based on this recording.
This is necessary for the Guitar Hero series because on a master track all instruments are separate tracks, which is required so the guitar sounds can be separate from the rest of the music.
In Guitar Hero II, a master track is shown by Performed by such as Stopas Performed byJane's Addiction. In Guitar Hero III, a master track is indicated as "by".