The major-minor system is a method used in music theory to classify scales and chords. In this system, a major scale is characterized by a specific pattern of whole and half steps, creating a bright and happy sound. Conversely, a minor scale has a different pattern, resulting in a darker and more somber tone. This system is fundamental in Western music, influencing the construction of harmony and melody. Composers often use major and minor chords to evoke different emotions in their pieces. Understanding this system helps musicians create and interpret music effectively.