In the previous examples, the melody consisted entirely of notes from the major scale. However, many melodies use notes from outside the major scale, particularly in styles such as Blues, Jazz, Rock and Funk.
These "outside notes" relate to the chromatic scale starting on the same note as the major scale of the key the music is written in. Therefore, if you have a piece of music in the key of C which contains notes which are not in the C major scale, you can relate these notes to the C chromatic scale.
This example demonstrates one octave of the C chromatic scale. The notes played with the slide depressed have an S under them, with the correct hole number written underneath.