What Are Natural Notes, Natural Signs and Accidentals?

Natural sign
Natural sign. Public Domain, Link

In music there is such a thing called "musical alphabet," this means each note has a name based on the alphabet. There are seven letters used in a musical alphabet namely: C - D - E - F - G - A - B - C. These seven letters are called the natural tones, on a piano/keyboard these are the names of the white keys. The white key to the left of two black keys is always a C, the next key to the right is always a D, next to that is E and so on.

Sharps and flats are also called accidentals. The symbol for a flat is like a lower case b, while the symbol for a sharp is like a pound sign (#). To flat a note means to lower it by one half step; to sharp a note means to raise it one half step. Accidentals are placed in front of the note they alter. The effect of accidentals last for the entire measure if it is used at the beginning of a measure. Its effect is cancelled by a bar line.

A natural sign is used to cancel out any key that is sharped or flatted. As an example, if a note is in C sharp a natural sign will bring the note back to its natural tone which is C. In the same way, if a note is in F flat, a natural sign will bring back that note to its natural tone which is F.