In many Asian musical traditions mode may be interpreted as a melodic model or basis for composition and improvisation. In India, for example, a raga is a mode that is identified not only by its characteristic ascending and descending tone patterns and motifs, but also by the ornamentation, embellishment and degrees of emphasis associated with specific tones. These modal elements form the musical material with which a performer will improvise. Furthermore, each raga is related to a particular mood, sentiment, time of day, season and other extra-musical factors. These factors, known in advance from tradition, affect both the performers as they improvise on the raga and the listeners as they experience the music.
Modality is also a crucial element in melodic recognition.
In Western music, the identity of a melody is determined by a unique and invariable succession of tones. However, in the art music of many Oriental traditions the same melody may exist in several different modes, and consequently may comprise several contrasting tone sequences. Its identity, therefore, is related more to its contour than to its precise tonal constituents. Finally, in jazz terminology, 'modal jazz' refers to a style of improvisation that emerged during the late 1950s, and in which melodic improvisation, instead of being conditioned by conventional harmonic structures, is based on modal principles. Actual Bloomsbury Guide to Human Thought 2.