A music scale usually refers to a progression of single notes upwards or downwards in steps. The word “scale” comes from the Latin “la scala” which means “ladder”, so a musical scale is a ladder of notes that runs from the root note to the octave note (octave means “eight”, as in octopus, octagon, etc., so eight notes.) Most beginners in music are introduced to the concept of scales very early in their training. Despite this, it sometimes takes a few years of training to get good understanding of how scales work.

A scale begins with a root, called the tonic. In a C scale (the first one most beginning musicians learn) the tonic note is “C.” The scale progresses either up or downward until it reaches the same note in the next octave. The C scale is an easy example. It begins with the tonic C. Going upward, the notes following are D, E, F, G, A, B and C. Downward, the note progression is C, B, A, G, F, E, D and C. The C scale has a total of eight notes. The distance from the tonic note to the next note of the same name is referred to as an octave. A scale in eight notes is called a diatonic.

Most modern instruments, including the piano, actually contain 12 notes in an octave. This is because semitones are included. The notes that comprise the semitones on a piano in a C scale are the black keys. A scale that includes the semitones is known as a chromatic scale. A chromatic C scale going upwards would be C, C sharp, D, D sharp, E, F, F sharp, G, G sharp, A, A sharp, B and C. Downward, the notes are C, B, B flat, A, A flat, G, G flat, F, E, E flat, D, D flat and C.

A pentatonic scale is scale of five notes. Pentatonic scales are not often used in Western music. The major exception to this rule would be in American blues and some rock music. They are preferred in other cultures though, such as Asian. Pentatonic scales are also common in Celtic and African music. Less common are hexatonic (six steps) and heptatonic scales (seven steps). Scales may also be octatonic (containing eight steps). These are commonly found in modern classical and jazz music.

The intervals between the notes on any scale (diatonic, chromatic, etc.) determine the type of scale. An interval is defined as the distance between two notes. They are also sometimes referred to as steps. Scales can be major (M), minor (m), perfect (P), augmented (A) or diminished (d or dim). The type of scale is determined by the size of the intervals. Interval sizes can be unisons, seconds, thirds, fourths, fifths, sixths and sevenths. Major and minor scales are 2nds, 3rds, 6ths, and 7ths. Unisons, 4ths, 5ths and octaves are perfect.

Sometimes scales may be referred to as modal. A simple definition of a modal scale is a series of notes in a scale, but which lack a primary or tonic note. Therefore many scales may have several modes. For example, every major scale actually has seven different modal scales.

It can take several years of training before a musician gets a good handle on scales and chords. However, even the youngest and newest of musicians use scales and the principles behind them every day. Mastering their theory may come later. Of course, every musician knows that only practice makes perfect!