Constructed languageA constructed language (shortened to a conlang) is a language whose phonology, grammar, and vocabulary, instead of having developed naturally, are consciously devised for some purpose, which may include being devised for a work of fiction. A constructed language may also be referred to as an artificial, planned or invented language, or (in some cases) a fictional language. Planned languages (or engineered languages/engelangs) are languages that have been purposefully designed; they are the result of deliberate, controlling intervention and are thus of a form of language planning.
LojbanLojban (pronounced ˈloʒban) is a logical, constructed, human language created by the Logical Language Group which aims to be syntactically unambiguous. It succeeds the Loglan project. The Logical Language Group (LLG) began developing Lojban in 1987. The LLG sought to realize Loglan's purposes and further improve the language by making it more usable and freely available (as indicated by its official full English title, Lojban: A Realization of Loglan).
Linguistic relativityThe idea of linguistic relativity, also known as the Sapir–Whorf hypothesis səˌpɪərnbspˈhwɔːrf , the Whorf hypothesis, or Whorfianism, is a principle suggesting that the structure of a language influences its speakers' worldview or cognition, and thus individuals' languages determine or shape their perceptions of the world. The hypothesis has long been controversial, and many different, often contradictory variations have existed throughout its history.
Engineered languageEngineered languages (often abbreviated to engelangs, or, less commonly, engilangs) are constructed languages devised to test or prove some hypotheses about how languages work or might work. There are at least three subcategories, philosophical languages (or ideal languages), logical languages (sometimes abbreviated as loglangs), and experimental languages. Raymond Brown describes engineered languages as "languages that are designed to specified objective criteria, and modeled to meet those criteria".
International auxiliary languageAn international auxiliary language (sometimes acronymized as IAL or contracted as auxlang) is a language meant for communication between people from all different nations, who do not share a common first language. An auxiliary language is primarily a foreign language and often a constructed language. The concept is related to but separate from the idea of a lingua franca (or dominant language) that people must use to communicate.
