Grammar contributes to producing meaning by encoding semantic distinctions in forms that are systematic. The predictability resulting from systematization allows language users to produce and understand new words and meanings by applying their knowledge of the language’s grammatical categories.

Languages differ widely in whether categories are encoded through the use of categories or lexical units. However, several categories are so common as to be nearly universal. Such universal categories include the encoding of the grammatical relations of participants and predicates by grammatically distinguishing between their relations to a predicate, the encoding of temporal and spatial relations on predicates, and a system of grammatical person governing reference to and distinction between speakers and addressees and those about whom they are speaking.