BONUSTRACK
Bonus track
In terms of recorded music, a bonus track is a piece of music which has been included on specific releases or reissues of an album. This is most often done as a promotional device, either as an incentive to customers to purchase albums they might otherwise not, or to repurchase albums they already own. In contrast to hidden tracks, bonus tracks are included on track listings and usually do not have a gap of silence between other album tracks.The above text is a snippet from Wikipedia: Bonus track
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