The Beastie Boys about music samples and a « frivolous » lawsuit against them :

Two things come into question when one is clearing a sample: the composition, and the sound recording. It is very important to understand the distinction between these two things in order to understand this case. A composition is a combination of words and musical notes, generally presented as sheet music. The copyright of the recording on the other hand, has to do with the uniqueness of the performance on that particular recording. The system exists because often songwriting and performing are two different lines of work.