 Key (music)

In music theory, the key of a piece is the group of pitches, or scale, that forms the basis of a music composition in classical, Western art, and Western pop music.The group features a "tonic note" and its corresponding "chords", also called a "tonic" or "tonic chord", which provides a subjective sense of arrival and rest, and also has a unique relationship to the other pitches of the same group, their corresponding chords, and pitches and chords outside the group.