Indian classical music's origins can be found in the Vedas, which are the oldest scriptures in the Hindu tradition. Indian classical music has also been significantly influenced by, or syncretised with, Indian folk music and Persian music. The Samaveda, one of the four Vedas, describes music at length. The Samaveda was derived from the Rigveda so that its hymns could be sung as Samagana; this style evolved into jatis and eventually into ragas. Bharat's Natyashastra was the first treatise laying down fundamental principles of dance, music, and drama.
It is a series of five or more musical notes upon which a melody is made. However, it is important to remember that the way the notes are rendered in musical phrases and the mood they convey are even more important in defining a raga than the notes themselves. In the Indian musical tradition, rāgas are associated with different times of the day, or with seasons. Indian classical music is always set in a rāga. Non-classical music such as popular Indian film songs and ghazals sometimes use rāgas in their compositions.
Joep Bor of the Rotterdam Conservatory of Music defined Raga as "tonal framework for composition and improvisation."Nazir Jairazbhoy, chairman of UCLA's department of ethnomusicology, characterized ragas as separated by scale, line of ascent and descent, transilience, emphasized notes and register, and intonation and ornaments.