In music, a sketch is an informal document prepared by a composer to assist in the process of composition. Sketches may range greatly in scope and detail, from the smallest snippets to full drafts; concerning Ludwig van Beethoven's sketchbooks, for instance, Dean writes that they "include every imaginable state between unaccompanied melodic motifs of a few notes to thoroughly worked-out full scores; even his fair copies of essentially 'finished' works show the signs of continuing composition."