Musical notation its "natural" form, which means that any sharps or flats applying to that note from the key signature or from accidentals are cancelled. Sometimes a courtesy accidental is used in music where it is not technically required, to remind the musician of what pitch the key signature requires. Following the key signature is the time signature. The time signature typically consists of two numbers, with one of the most common being "4/4". The top "4" indicates that there are four beats per measure (also called bar). The bottom "4" indicates that each of those beats are quarter notes. Measures divide
Key signature signature that appears at the end of a line immediately before a change is usually preceded by an additional barline; the line at the very end of the staff is omitted in this case. If both naturals and a new key signature appear at a key signature change, there are also more recently variations about where a barline will be placed (in the case where the change occurs between bars). For example, in some scores by Debussy, in this situation the barline is placed after the naturals but before the new key signature. Hitherto, it would have been more usual