We started this article by defining notes as the basic unit of music. There are usually 22 frets on a banjo so this is the total number of different notes we can play on a single string. If we took out the frets we could play a different tone anywhere we put our finger. If we did this we could play an infinite number of different notes! Fortunately we do have frets.

When you pick the open 3rd string you are playing a G note. If move up the 12th fret on this string you are also playing a G note, except we say that this G is an octave higher than the G on the open string. From the standpoint of the string's vibration rate, the frequency is exactly double what it was when the string was not fretted. The name “octave” refers to the fact that a major scale contains 7 different note PLUS the next higher version of the first note of the scale being played giving use a total of 8 notes. It's like the word “octopus” refers 8 legs and and “octogon” has 8 sides. In banjo terms it means that any note played below the twelfth fret repeats itself twelve frets higher on the same string(unless you run out of frets).

In Western music we limit the possible number of notes to eleven. These include the notes A, B, C, D, E, F, and G. Not very creative names for the notes. In Europe and much of the world they use the Do, Re, Mi system called solfege hence the song about deer and rays of golden sun. In addition to the notes that just use letters we have the notes that are called either sharps or flats. We usually think of these in terms of the piano keyboard. The letter notes are the white keys and the sharps and flats are the black keys. There are fewer black keys that white ones (we'll come back to this later). The total of 7 “natural” notes (the white keys) and 5 sharps and/or flats plus the octave of wherever you start are what we call the chromatic scale.

As we'll see later, all twelve of the notes of the chromatic scale (including the octave note) almost never get used in most styles of music including bluegrass. The scales we commonly use (more about scales later) have seven notes and repeat at the eighth (which is where the term octave comes from, like in octagon or octopus). This limits the possible number of notes we normally have to worry about to just seven. We may use some of the others, but we're heading in the right direction.