Question

what do you understand by criteria

Answer 1

a principle or standard by which something may be judged or decided.

Answer 2

Like some other nouns borrowed from the Greek, criterion has both a Greek plural, criteria, and a plural formed on the English pattern, criterions. The plural in -a occurs with far greater frequency than does the -s plural: These are the criteria for the selection of candidates. Although criteria is sometimes used as a singular, most often in speech and only infrequently in edited prose, in standard English, it is more clearly used as a plural with criterion as the singular.