Sharp and Flat Notes
A sharp (#) raises the pitch of a note by one semi-tone. A flat (b) lowers the pitch of a note by one semi-tone. In music notation the # and b signs (called accidentals) are always placed before the note heads.
This example illustrates that the same note has two different names (i.e., F# and Gb have the same position on the keyboard). These are referred to as enharmonic notes. Other examples of enharmonic notes are: A#/Bb, C#/Db, D#/Eb, F#/Gb,G#/Ab. (This principle also applies to the naming of chords e.g., A #Major = Bb Major, C#m7 = Dbm7 etc.)
A natural (@) cancels the effect of a sharp or flat. A sharp or flat, when placed before a note, affects the same note if it recurs in the remainder of the bar. It does not, however, affect notes in the next bar, e.g.:
With the inclusion of sharps and flats, there are 12 different notes within one octave, e.g.:
Note that there are no sharps or flats between B and C, and E and F.
