Raga (राग) (rāg /राग (Hindi), raga (Anglicised from rāgaḥ/रागः (Sanskrit)) or rāgam /ராகம் (Tamil)) are the very detailed melodic modes used in Indian classical music. Traditionally, ragas are based on an intricate Vedic philosophy of sound.

A raga is basically a set of Vedic-rooted rules for how to build a melody. It specifies rules for movements up (aarohanam [आरोहणम्]) and down (avarohanam [अवरोहणम्]) the scale, which notes should figure more and which notes should be used more sparingly, which notes may be sung with gamaka, phrases to be used, phrases to be avoided, and so on.¹ The result is a framework that can be used to compose or improvise melodies, allowing for endless variation within the set of notes.

The underlying scale is a five, six or seven tone-scale, made up of swaras. This provides one method of classifying ragas. Ragas that have five swaras are called audava (औडव) ragas; those with six, shaadava (षाडव); and with seven, sampoorna (संपूर्ण) (Sanskrit for 'complete'). Those ragas that do not follow the strict ascending or descending order of swaras are called vakra (वक्र) ('crooked') ragas. (To see the order of notes, check the article on swara.)

In the seven tone-scale the second, third, fourth, sixth, and seventh notes can be sharp or flat, making up the twelve notes in the Western equal tempered chromatic scale. However, ragas can specify microtonal changes to this scale: a flatter second, a sharper seventh, and so forth. Furthermore, such variations can occur between styles, performers or simply follow the mood of the performer. There is no absolute pitch; instead, each performance simply picks a ground note, which also serves as the drone, and the other scale degrees follow relative to the ground note.

Every time of the day, morning, afternoon, evening and night, has its specific ragas. This distinction is strictly followed in Hindustani music (practised in North India), but is by and large ignored in Carnatic music (practised in South India).

The two streams of Indian classical music, Carnatic music and Hindustani music, have independent sets of ragas. There is some overlap, but more "false friendship" (where raga names overlap, but raga form does not). In north India, the ragas have recently been categorised into ten thaats or parent scales (by Vishnu Narayan Bhatkhande, 1860-1936); South India uses an older, more systematic classification scheme called the melakarta classification, sporting 72 parent (melakarta) ragas. Overall there is a greater identification of raga with scale in the south than in the north, where such an identification is impossible.

As ragas were never codified but transmitted orally from teacher to student, some ragas can vary greatly across regions, traditions and styles.

Indian classical music is always set in raga, but all raga music is not necessarily classical. Many popular Indian film songs are themselves based on ragas.

Footnotes

1. Nothing other than the aarohanam and avarohanam are ever actually written down (or even taught directly); if such things are written, they are mostly neglected. The subtle rules of where to give gamakas to notes, what phrases are traditional, and so on are usually codified in special songs called varnams. These songs show the characteristics of the ragam in practice and are transmitted orally.

External link

• The Raga Guide (http://www.wyastone.co.uk/nrl/world/raga/) (sections)