have however shown great assimilative power, constantly embraced folk
tunes and regional flavours, and raised many of them to the status of ragas.
Despite both of them flourishing individually in their own stream, both these
systems have had strong mutual influence on each other.
Raga and Thala Concepts
The Concept of Raga Raga and Thala are the two pillars of the Indian
classical music. Raga forms the basis of melody and Thala forms the basis of
rhythm. Each melodic structure of Raga comprises something analogous to a
distinct personality subject and a prevailing mood. Ragas have several
important elements. The first of them is sound, referred to as nada. Among
the five elements of creation, nada represents the first element, known as the
element of space. This is followed by the next element, pitch, which
represents swara (tones), and sruti (microtones). Raga also produces rasa, the
emotional effects in the performer and listener. Raga aims at eliciting
emotional and psychological responses from the listener, and these specific
responses are best understood from the concept of rasa, which are of nine
types: love (shringar), humour (hasya), pathos (karuna), anger (raudra),
heroism (vir), terror (bhayanaka), disgust (veebhatsa) and wonder (adbhuta).
    The foundation stone of classical music is raga, which in turn is based on
72 "melas", or parent scales. The principle of raga constitutes the combination
of notes selected out the 22 note intervals of the octave. Every Raga is based
upon some Thaat or Scale. The principal moods of raga include tranquility,
devotion, eroticism, loneliness, pathos, and heroism. The timing of
performing a raga depends upon its mood, and accordingly it is performed at
a particular time of the day, night or a season. While performing, a performer
combines shrutis and notes to produce the desired emotions.
    There are three categories of ragas: (a) Odava or pentatonic, which
means a composition of five notes, (b) Shadava or hexatonic, that defines it
as a composition of six notes, and (c) Sampoorna or heptatonic, which is a
composition of seven notes. Every raga is necessarily required to have at
least five notes. These notes start at Sa, have one principal note, a second
important note and a few helping notes. The principal note or the "King" is
the note on which the raga is built. There are various ways to stress upon the