Notes are the musical notation representing a fixed pitch. While the word strictly refers to the physical notation of a pitch, it’s more commonly used to refer to both the pitch and the notation. Â Â Â  Notes are named after the first seven letters in the alphabet — A, B, C, D, E, F, and G — and keep the same letter value as they are repeated up or down the keyboard or other musical instrument.

     But since there are twelve notes in a diatonic scale, the seven notes can be altered. To get the extra five notes,we sharp notes(raise by a half-step) and flat notes (lower by a half-step); the sharped and flatted notes are the black keys on a piano. All notes can be altered this way, but a C flat is enharmonic with B, a white key, and B sharp is enharmonic with C — a white key.Likewise E sharp is enharmonic with F — also a white key, and of course F flat is enharmonic with E, a white key.

     The types of notes and their values are based on the amount of time they take up in a song and are named in a hierarchy of values:

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