A scale is a chosen subset of the 12 notes, and it works like a painter’s palette: the notes a piece keeps returning to.
Most songs use seven of the twelve notes at a time. Which seven, and how they space out, decides whether the music sounds bright, dark, bluesy or folk-like.
The major scale is the most common palette; the minor scales are its shadowed siblings. Ear training teaches you to recognize the palette itself, not just individual notes.
Common questions
What is a scale in simple terms?
A scale is the set of notes a piece of music mainly uses, arranged in order. It functions like a color palette for melody and harmony.