Simplify the following text for a Grade 9 native English-speaking person.
Original: More specifically , in musical notation , sharp means `` higher in pitch by a semitone ( half step ) , '' and has an associated symbol , which may be found in key signatures or as an accidental , as may flats .
Simplified: In musical notation , sharp means `` higher in pitch by a semitone ( half step ) , '' and looks like this : .