The two main traditions of classical music are Carnatic music found in the southern region, and Hindustani music, found in the northern and central regions. Both traditions claim Vedic origin, and history indicates that they diverged from a common musical root since about the 13th century.
Indian classical music is categorized under two genres. These are Hindustani and Carnatic. Broadly speaking, Carnatic music developed in the south of the country, while Hindustani is indigenous to the north.
Hindustani music is based on the raga system. A raga is a melodic scale, consisting of notes from the basic seven known as sa, re, ga, ma pa, dha, and ni. Apart from sa and pa which are constant, the other notes may be in major or minor tone, and this gives rise to innumerable combinations. Ten basic scales or that are recognized, and other ragas are considered to have evolved from these. A raga must contain a minimum of five notes.
Depending on the notes included in it, each raga acquires a distinct character. The form of the raga is also determined by the particular pattern of ascent and descent of the notes, which may not be strictly linear. Melody is built up by improvising and elaborating within the given scale. The improvisation is at times rhythm bound and at other times free from any overt rhythm.
Formal compositions (songs or instrumental compositions in a fixed meter) are juxtaposed with the improvised portion. Khyal and Dhrupad are two major types of compositions within the Hindustani genre. Of the two, Dhrupad is an older form and requires rigourous training in rhythm control as well as voice culture. Khyal developed as a more popular alternative as it contains both slow and lively compositions, though it retains its totally classical character.