Source: Far Out. Interesting read on the origins of this common practice.
Tape looping was a method first introduced in the 1940s, with French composer Pierre Schaeffer often given due credit for his pioneering musique concrète. These experimental compositions were created by splicing up tape recordings and rearranging them into a sonic collage. Much like the William Burroughs of sound, Schaeffer formed his early collages from everyday vibrations, such as those produced by the human body, vehicles or kitchen utensils.