A scale, from the Latin word Scala meaning "a ladder," is a series of tones arranged according to a certain prescribed plan or order. The evolution of their mode, or arrangement, as we know them today, extends over many centuries and provides an interesting and important development in the history of music. Scales have changed, not only from time to time, but from place to place.
Ancient Arabians divided their scale into seventeen tones; Chinese used? among no thers, a five-tone or pentatonic scale; and Hindus utilized as many as twenty- two tones. The ancient Greeks employed eight modes. Our modern scales, which we inherited from the Greeks, consist of eight tones. In addition, we have one constructed within the octave (eight-tone scale) which has twelve tones and is known as the chromatic scale. In modern terminology it is often referred to as the duodecuple scale. Some composers also use a scale of six tones, or a whole-tone scale.’

Much of the music we hear, however, is based on the eight-tone scales that have been in use since about the seventeenth century when the tempered scale came into practice. These are called the major and minor modes and are constructed on patterns of successive intervals one-whole step or one-half step apart. It is the difference in the sequence of the intervals that makes their individuality. The major scale conforms to one set pattern, but the minor has three forms, —natural, melodic, and harmonic.

With some composers a song is either major or minor. With others there is an intermingling of the two. For example, Schubert and Franz used first one and then the other at will to express the mood of the composition. Sir George Grove said: ”With Schubert the minor mode seems to be synonymous with trouble and the major with relief; and the mere mention of the sun or a smile or any other emblem of gladness is sure to make him modulate. Yet one should not assume that the major mode always expresses gladness and the minor mode sorrow. In fact, the reverse is sometimes true. However, as a rule, the minor mode is used by composers to express sorrow and mystery, and the major is used to portray joy and brightness.