In Western music, we split the octave up into 12 different pitches. These twelve pitches are used to create almost all of our music.
One of the best ways to learn about how we think about these twelve pitches is to look at the piano keyboard where they are clearly laid out for us.
The first thing you might notice is that the white and black keys follow a certain pattern and this helps us to understand how the 12 basic pitches are organised. The white notes on the piano are named after the first seven letters of the alphabet - A B C D E F G.
The black notes fill in the pitches between these letter named notes. We talk about these notes as being - flats and sharps.