3.b.1) Note Scales and Key Signature

3.a.3) Scale 

Scale is a fixed set series of pitches in a form of ascending and descending tones within an octave (frequency band). Scale is used as a reference point for musical tuning, harmonic grammar, and genre identity. There are many types of scale such as pentatonic scale, modal scale, chromatic scale and the most common scale in Western classical art music is diatonic scale.

3-tuning
Figure 3.a.1 Diatonic scale

Series of note pitches in a scale are set according to a certain ‘scale degree’ in form of semitone, tone  or a mixture of both.