The soundness of a system, primarily mathematical in character, consists of its internal coherency, logical rigidity and numeric accuracy. The tala system in Carnatic music satisfies all these conditions and is not only perfect but also beautifully elastic.
There are six parts (Angas - limbs) of a tala but the following three are used more frequently:
U - Anudrutham, A beat, represented by the symbol "U". This is physically represented as 1 unit
0 - Drutham, A beat and a wave of the hand, represented by the symbol "O". This is physically represented as 2 Unit.
| - Laghu, A beat followed by finger counts starting from the little finger. It is represented by the symbol "l". Laghu can be of five types (Jaati) depending on the number of units.
Chaturasra (Jaati) laghu has a beat plus 3 finger counts, which is a total of 4 units.
Tisra (Jaati) laghu has 3 units i.e. a beat plus 2 finger counts.
Misra (Jaati) laghu has 7 units, i.e. a beat plus six finger counts.
Khanda (Jaati) laghu has 5 units, i.e. a beat plus four finger counts.
Sankeerna (Jaati) laghu has 9 units, i.e. beat plus eight finger counts.