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G sharp
F Sharp usually, but sometimes it can be G flat
No. On a certain note with both a sharp and flat, (G, for example) they are the same distance from G, but going in diferent directions. G sharp raises the note by one half step while G flat lowers the note by one half step. However, it is possible for a sharp note to mean the same note as a flat note. For example, G sharp is the same note as A flat. This is called being enharmonic.
G#
G#
Its a kind of note in music. Its also in the G-scale of g sharp it is on the grand staff on piano.
A flat. Because this note is between G and A, you can go up from G (make it a sharp) or down from A.
C sharp, D sharp, E natural, F sharp, G sharp, A natural, B sharp & C sharp We call the note C "B sharp" to avoid using the same letter name twice. If we used the note name "C" we would have 2 C-notes and no B-notes in the scale!
One half step above G is G-sharp (or A-flat). In musical terms, this means that if you move up from G to the next closest note, you reach G-sharp/A-flat.
A
C sharp
-------- A - 2nd A flat/G sharp - 3rd G - 4th -------- F - 1st F sharp/G Flat - 5th E - 2nd E flat/D sharp - 3rd -------- D - 4th D Flat/C sharp - 5th C - 6th -------- B - 7th B Flat/A Sharp - 1st A - 2nd A Flat/G sharp - 3rd -------- G - 4th