The following list of notable constructed languages is divided into auxiliary, ritual, engineered, and artistic (including fictional) languages, and their respective subgenres.
International auxiliary languages are languages constructed to provide communication among all human beings, or a significant portion, without necessarily replacing native languages.
Controlled natural languages are natural languages that have been altered to make them simpler, easier to use, or more acceptable in certain circumstances, such as for use by people who do not speak the original language well. The following projects are examples of controlled English:
Basic English, Special English and Globish seek to limit the language to a given list of common-use words and terms in order to make it simpler to foreign learners or other people who may have difficulties
Plain English proposes a more direct, short, clear language by avoiding many idioms, jargon and foreign words
Simplified Technical English seeks to largely reduce the complexity and ambiguity of technical texts (such as manuals)
E-Prime eliminates the verb to be with the intent of making writing more expressive and accurate.
Visual languages use symbols or movements in place of the spoken word. Sign languages fall in this category.
Blissymbols (zbl)
Gestuno
List of sign languages
These are languages (and scripts) in actual use by their communities or congregations.
Damin
Eskayan
Medefaidrin
An Essay towards a Real Character and a Philosophical Language by John Wilkins
aUI
Ilaksh
Isotype
Ithkuil
Láadan (ldn)
Loglan by James Cooke Brown
Logopandecteision
Lojban (jbo) successor to Loglan by the Logical Language Group
Toki Pona by Sonja Lang
Attempto Controlled English is a machine-readable subset of English that can be used as a knowledge representation language.
Several well known Knowledge Query and Manipulation Languages have been created from extensive research projects, to represent and query knowledge on computers:
Knowledge Interchange Format (KIF), a precursor for knowledge representation.
Common Logic (CL), an ISO standard derived from KIF.
Resource Description Framework (RDF), a language standardized by the World Wide Web Consortium (W3C) based on the principles of Common Logic, which represents knowledge as a directed graph built from unordered sets of "sentences" (in fact, as relational triples: subject, relation, attribute) using various syntaxes (XML, Turtle, JSON-LD, RDFa) for its interchange format. Each element of the triple can be either a simple value (if its semantic value is not specified outside of the relation using it), or identifiers of objects (such as URIs) that are part of enumeration built from another subset of relational triples. The relations may be open (in which case the attributes are not enumerable) or closed in a finite enumerable set whose elements can be easily represented as objects as well with their own identity participating in many different relations for other parts of the knowledge.
UML may be used to describe the sets of relations and rules of inference and processing, and SQL may be used to use them in concrete schemas and compact store formats, but RDF designs its own (semantically more powerful) schema language for handling large sets of knowledge data stored in RDF format.
RDF is most probably useful only for automated machine processing, but its verbosity and complex (for a human) representation mechanisms and inference rules does not qualify it as a human language except in very limited contexts. It is still a specification with extensive research.
Web Ontology Language (OWL), another knowledge representation language standardized by W3C, and derived from Common Logic.
CycL
The Distributed Language Translation project used a "binary-coded" version of Esperanto as a pivot language between the source language and its translation.
Lincos
Loom
Universal Networking Language (UNL)
Quenya
Sindarin
Taliska (unpublished)
Additionally, sketches of various other languages, such as Adûnaic, the Black Speech, Khuzdul, Telerin and Westron appear in his Middle-earth works alongside earlier draughts or imagined archaic forms of Elven languages such as Common Eldarin or Primitive Quendian, Goldogrin, and Ilkorin. Others such as Entish, Rohirric, and six languages of the Avari are mentioned but have only one or two words or phrases noted.
Baronh, language of Abh in Seikai no Monshō (Crest of the Stars) and others, by Morioka Hiroyuki.
Láadan (ldn), in Suzette Haden Elgin's science fiction novel Native Tongue and sequels.
Lapine, spoken by the rabbits in Watership Down by Richard Adams.
Nadsat slang, in A Clockwork Orange by Anthony Burgess.
Newspeak, a constructed language in Nineteen Eighty-Four by George Orwell.
Spocanian, in Rolandt Tweehuysen's fictional country Spocania.
Starsza Mowa from Andrzej Sapkowski's Hexer saga.
Zaum, poetic tongue elaborated by Velimir Khlebnikov, Aleksei Kruchonykh, and other Russian Futurists as a "transrational" and "most universal" language "of songs, incantations, and curses".
Bordurian, in some of Hergé's The Adventures of Tintin, mostly in The Calculus Affair.
Syldavian, in some of Hergé's The Adventures of Tintin, mostly in King Ottokar's Sceptre.
Film and television
Atlantean created by Marc Okrand for the film Atlantis: The Lost Empire.
Barsoomian, the language of the Martians in the 2012 film John Carter based on Edgar Rice Burroughs' novels.
Dothraki, created by David J. Peterson for the TV series Game of Thrones (based on the novel series A Song of Ice and Fire by George R. R. Martin).
Enchanta, in the Encantadia and Etheria television series in the Philippines, created by the head writer Suzette Doctolero.
Goa'uld, the galactic lingua franca from Stargate SG-1, supposedly influenced Ancient Egyptian.
Klingon (tlhIngan Hol), in the Star Trek films and television series, created by Marc Okrand.
Ku, a fictional African language in the 2005 film The Interpreter.
Na'vi, the fictional language spoken by the Na'vi in Avatar, created by Paul Frommer.
Pakuni, the language of the Pakuni from the Land of the Lost television series and film.
Parseltongue, the 'language of the snakes' in the Harry Potter series.
Tantalog, the language of the United Galactic Federation and Stitch's native language in the Lilo & Stitch franchise.
Tenctonese from the Alien Nation film and television series, created by Van Ling and Kenneth Johnson.
The Valyrian languages, created by David J. Peterson for the TV series Game of Thrones (based on the novel series A Song of Ice and Fire by George R. R. Martin).
The Verbis Diablo, created for the TV series Penny Dreadful.
Vulcan language from Star Trek. Further developed by fans as Golic Vulcan.
Shiväisith, created by David J. Peterson for the movie Thor: The Dark World is the language spoken in the movie by Dark Elves.
Kobaïan, created by Christian Vander, used by 1970s French rock group Magma.
Loxian, created by Roma Ryan, used on Enya's 2005 album Amarantine and 2015 album Dark Sky Island.
Moss, created by Jackson Moore in 2009, a language with a musical phonology, modeled on pidgins.
D'ni, language spoken by the subterranean D'ni people in Cyan Worlds' Myst series of computer games and novels.
Dovahzul, the primary non-English language used in the game The Elder Scrolls V: Skyrim, which has been refined and modernized by fans of the game.
Gargish, used in the Ultima computer game series, by the gargoyle race.
Tho Fan, in the Xbox game Jade Empire, created by Wolf Wikeley.
"Panzerese," a mix of Ancient Greek, Latin and Russian in the Panzer Dragoon series.
Tsolyani, by M. A. R. Barker in his world of Tékumel as described in the roleplaying game Empire of the Petal Throne.
Wenja, Udam and Izila are the three primitive dialects based on Proto-Indo-European in Far Cry Primal.
Furbish
Dritok, by Don Boozer
Kēlen, by Sylvia Sotomayor
Teonaht, by Sally Caves
Verdurian and several other languages created for the fictional planet of Almea by Mark Rosenfelder
Some experimental languages were developed to observe hypotheses of alternative linguistic interactions which could have led to very different modern languages. Two examples include:
Brithenig, created by the inventor of the alternate history of Ill Bethisad, Andrew Smith
Wenedyk, a language of the alternate history of Ill Bethisad created by Jan van Steenbergen
Talossan, by R. Ben Madison
Balaibalan by Muhyî-i Gülşenî
Enochian by Edward Kelley
Lingua Ignota, by Hildegard of Bingen
