An ideal language user a speaker/listener that is a member of a homogeneous speech community, knows the language perfectly, and is not affected by memory limitations or distractions. Such a speaker/listener does not exist in the real world. The ideal language user is a subject of most linguistic theories because linguist can only study an idealized version of a language (I-language) because in the real world people make performance mistakes while speaking. The term was coined by Noam Chomsky.