Accidentals
Sharps, flats and naturals — and the bar-line rule everyone forgets. · 10 min
The three accidentals
Sharp (♯) raises a note by one half step. Flat (♭) lowers by one half step. Natural (♮) cancels a sharp or flat and returns to the white key.
The symbol is written BEFORE the note on the staff, on the same line or space, but you say it after: "F sharp".
One key can have two names. C♯ and D♭ are the same key — these are called enharmonic equivalents. E♯ is F; C♭ is B.
Tap the keys. Highlighted: C#5, D#5.
The bar rule
An accidental applies to every later note on the same line or space for the rest of that bar. The bar line cancels it.
Below: the second F is still F♯ (no symbol needed). The third F needs a natural to go back to F. In the next bar, F is F again automatically.
The rule applies only to the same octave. An F♯ on the top line doesn't make the F in the first space sharp.
Check yourself
You'll see immediately whether each answer is right, and why.
A sharp raises a note by…