American linguist noam chomsky distinguished between competence and performance. Competence is what people know about their language: not produced by a group or population it resides in the individual. Performance is how people use that knowledge linguists are concerned with competence, not with performance. Linguists study the underlying system of language and an idealized form of what a speaker knows about their native language. Underlying system is called a grammar: each person develops a grammar of their language during acquisition. Psychologists study how people actually use language how that is influenced by a person"s language skills and by social situation, mood nd attention, among other things. In order to answer this question, we have to specify at least a working definition of language. Remembering our discussion of concepts, we could describe the concept language in terms of a set of features.