The Raag is the most illusive and the most important concept of Northern Indian Music. In essence a Raag is a set of predefined rules to build a melodic composition. In general, the following are the basic rules or characteristics of a Raag. These rules are described in a logical order:

1. A Raag must belong to one of the 10 Thaats of Northern Indian Music.
2. A Raag must have an ascending (aroh) and a descending (Avroh).
3. Every Raag’s Aroh and Avroh (ascending and Descending) must not contain less than five or more than 7 notes. This rule defines the Jati of a Raag. Read more about Jaties here.
4. A Raag’s notes must sound pleasant to the ear. Although this rule may sound very vague, but it is always mentioned in the set of rules. The reason being that theoretically there are so many Raags possible in a Thaat, but all those set of notes do not sound great together.
5. A Raag must have a Vadi and Samvadi note.
6. A Raag’s Vikrat notes and the Vivadi note must be defined.
7. A Raag must have a main phrase (Pakad).
8. A Raag’s flow must be defined and it should be unique. This rule defines how the notes are used according to a Raag’s Aroh/Avroh and Jati. Two Raags may have the same notes, the same ascending, the same descending and the same jati, if they have different Vadi and Samvadi notes, then the Pakad and flow of notes will change. Thus making them two unique Raags.Once all the above rules are defined the following rules automatically come into effect:
9. According to the Time Theory of Indian Raags, Every Raag has a Time slot of at least 3 hours.
10. There are many similar Raags that share some of their properties. When performing a particular Raag, knowing the other related Raags is very important.

These are the basics. Although we are only talking about the ‘basic Theory of Northern Indian music’, but I feel I must write a little more about the Raag concept. This is the heart of Indian music. So I will dedicate even my next post to the properties of a Raag.

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