The rhythmic element in a Hindustani music composition is called a Tala. Its main function is to interpret geophysical time as musical time. Like geophysical time, a Tala is also cyclical. But, as musical time, subordinated to the human aesthetic sensibility, it can be given any duration and tempo, and can also be sub-divided in a variety of ways. It can thus be imparted different cycle durations and cadential patterns.
The art and craft of the composer arranges a convergence of these cycle durations and cadential patterns with the meter of the melodic lines, and the poetic verse (where present). This convergence of the three elements imparts to each composition its distinctive form.
Twentieth century literature lists about 50 tala-s. However, across all genres, contemporary Hindustani music is dominated by ten to twelve Tala-s. The smallest Tala in circulation has 6 beats, while the longest has 18 beats. The subdivisions of the Tala-s can be regular or irregular. Some Tala-s are particularly suited for slow-tempo compositions, while others are specially suited for medium or brisk tempo compositions. A few, very few, Tala-s are versatile enough to be performed at any tempo without losing their distinctive cadential structure.