Major scale

The major scale or Ionian scale is one of the most commonly used musical scales, especially in Western music. It is one of the diatonic scales. Like many musical scales it is made up of seven notes: the eighth duplicates the first at double its frequency so that it is called a higher octave of the same note (from Latin "octavus", the eighth).

The simplest major scale to write is C major, the only major scale to not require sharps or flats:

The major scale had a central importance in European music, particularly in the common practice period and in popular music, owing to the large number of chords that can be formed from it. In Carnatic music, it is known as Dheerasankarabharanam, and in Hindustani classical music it is known as Bilaval.

A major scale is a diatonic scale. The sequence of intervals between the notes of a major scale is:

where "whole" stands for a whole tone (a red u-shaped curve in the figure), and "half" stands for a semitone (a red broken line in the figure).

A major scale may be seen as two identical tetrachords separated by a whole tone. Each tetrachord consists of two whole tones followed by a semitone:

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