Many modern musicologists believe that there are only 10 usable Thaats in modern Northern Indian music. Although there are many popular Raags today, that do not comply with this theory. Pundit Bhatkhande devised a system to assign Thaats for such Raags based on their usage of the following notes:
‘r’ and ‘d’ komal
‘R’ and ‘D’ shudh
‘g’ and ‘n’ komal
The above division of Raags is born out of the ‘Raag-Time Theory’. This system works fine as long as one is well versed in both theories (Thaat system and Time Theory). Mathematically this system has no value. The Thaat System was devised on usage of notes in a certain fashion (mathematically). A Raag should not have any notes that do not exist in its parent Thaat. To find the solution to this problem, we are going back to the original Thaat system. According to which there are 32 Sampooran Thaats. This Ragkosh is based on that theory. Still,
special attention has been paid to mention the popular Thaat for those Raags which have been categorized under another than their original Thaat.