Sampling is a common practice in the music industry.  Generally, it means the use of pieces of songs created by other artists in a song of your own, and it has been widely used ever since technology allowed for the possibility of it, especially in the hip-hop scene.  Some people view it as a cop-out, something done by someone too lazy to create their own piece.  This is just one of many arguments against it, but many more claim that it’s an art form in its own right.  I agree with the latter.  Sometimes the use of audio clips from other songs can enhance a piece, give it more meaning than it would otherwise have.  Part of this comes from the community of the music industry, from knowing what the other song was meant to stand for and what it did in society, and using that context to add to something else.  Art is meant to be shared.  Sampling is just an extension of this sentiment.  Using something that already has an established significance to give more meaning to something new is just as artistically important as completely original works.  Being able to understand and apply that kind of context to something new is its own art form.