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.
Latino sine flexioneLatino sine flexione ("Latin without inflections"), Interlingua de Academia pro Interlingua (IL de ApI) or Peano's Interlingua (abbreviated as IL), is an international auxiliary language compiled by the Academia pro Interlingua under the chairmanship of the Italian mathematician Giuseppe Peano (1858–1932) from 1887 until 1914. It is a simplified version of Latin, and retains its vocabulary.
InterlinguaInterlingua (ɪntərˈlɪŋɡwə; ISO 639 language codes ia, ina) is an international auxiliary language (IAL) developed between 1937 and 1951 by the American International Auxiliary Language Association (IALA). It ranks among the most widely used IALs and is the most widely used naturalistic IAL – in other words, those IALs whose vocabulary, grammar, and other characteristics are derived from natural languages, rather than being centrally planned.
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.
EsperantoEsperanto (ˌɛspəˈrɑːntoʊ or ˌɛspəˈræntoʊ) is the world's most widely spoken constructed international auxiliary language. Created by the Warsaw-based ophthalmologist L. L. Zamenhof in 1887, it is intended to be a universal second language for international communication, or "the international language" (la Lingvo Internacia). Zamenhof first described the language in Dr. Esperanto's International Language (Unua Libro), which he published under the pseudonym Doktoro Esperanto.