Mātrika metre's are based on units of prosodic time (mātrā) rather than groups of syllabes, vārnika metres.
[1] The unit of measurement is the mātrā, or beat, from which it takes its name.
In recitation, however, long vowels may be pronounced as short, or short as long, in order to fit the words into the desired metre.
For this reason, the mātrā count does not always correspond exactly to the written vowel arrangement.
Different mātrika metres have different rules determining caesurae; most require a specific pattern of rhyme.