Accidentals (sharp ,
and natural )
alter the pitch of the next note as well as notes written on the same staff-line
up to the next bar-line.
Accidentals written at the start of a staff line denote the key in which
a tune is written, and are valid for all following bars, up to a key-change (if
In keys with lots of sharps, flats double sharps and double
flats will be used occasionally.
In non-western music and some contemporary music half sharps and half
flats are used sometimes
Accidentals may be entered with the accidental-menu , but are generally
entered more easily using the pitch increment / decrement keyboard shortcuts
<+> and <-> respectively.
Courtesy accidentals may be used when you feel they are appropriate.