Enharmonic Spelling of Pitches

Enharmonic

A pitch can be notated, or spelled, in more than one way.  This is easily demonstrated on a keyboard.  Accidentals are used to move a note up or down by a half step or two.  For example, an F-sharp is the same note as a G-flat spelled enharmonically.  It is the black key between the F and the G.  If you proceed down a half step from C to C-flat, that note is also called B-natural.  Likewise, E-sharp is the same as F-natural, spelled enharmonically.  This illustrates that flats and sharps can be white keys on the keyboard.  F-flat is the same pitch as D-double sharp, and E-natural.  Enharmonic spellings occur whenever a pitch is notated by a different name than would be ordinarily used in a given key.