Orchestration's the study or practice of writing music for an orchestra (or, more loosely, for any musical ensemble) or of adapting for orchestra music composed for another medium. It only gradually over the course of music history came to be regarded as a compositional art in itself. There're two general kinds of adaptation: transcription, which closely follows the original piece, and arrangement, which tends to change significant aspects of the original piece. In practice, however, the terms… (More on Orchestrator)