Reading Music : Accidentals
All the notes we have seen so far correspond to the white keys of the piano keyboard.
Here we show how the white keys of the piano are written on the staff:
How do we write the black keys?
Let's take an example. The black key between the C and D keys can be written by placing the sharp 
accidental symbol in front of the C or the flat 
accidental symbol in front of the D. The other keys can be written in a similar way:
The distance between one key and the next is called a half step. The sharp symbol raises a note by a half step, while the flat symbol lowers the note by a half step.
For more information see:
Translated by Dan Román, revised by Sue Talley.
