Controlled natural language in the context of "ASD Simplified Technical English"

A natural language or ordinary language is any spoken language or signed language used organically in a human community, first emerging without conscious premeditation and subject to: replication across generations of people in the community, regional expansion or contraction, and gradual internal and structural changes. The vast majority of languages in the world are natural languages. As a category, natural language includes both standard dialects (ones with high social prestige) as well as nonstandard or vernacular dialects. Even an official language with a regulating academy such as Standard French, overseen by the Académie Française, is still classified as a natural language (e.g. in the field of natural language processing), as its prescriptive aspects do not make it regulated enough to be considered a constructed or controlled natural language. Linguists broadly consider writing to be a static visual representation of a particular natural language, though, in many cases in highly literate modern societies, writing itself can also be considered natural language.

Excluded from the definition of natural language are: artificial and constructed languages, such as those developed for works of fiction; languages of formal logic, such as those in computer programming; and non-human communication systems in nature, such as whale vocalizations or honey bees' waggle dance. The academic consensus is that particular key features prevent animal communication systems from being classified as languages at all. Certain human communication or linguistic systems with no native speakers, as sometimes used in cross-cultural contexts, are also not natural languages.

This is a list of bodies that consider themselves to be authorities on standard languages, often called language academies. Language academies are motivated by, or closely associated with, linguistic purism and prestige, and typically publish prescriptive dictionaries, which purport to officiate and prescribe the meaning of words and pronunciations. A language regulator may also have a more descriptive approach, however, while maintaining and promoting (but not imposing) a standard spelling. Many language academies are private institutions, although some are governmental bodies in different states, or enjoy some form of government-sanctioned status in one or more countries. There may also be multiple language academies attempting to regulate and codify the same language, sometimes based in different countries and sometimes influenced by political factors.

Many world languages have one or more language academies or official language bodies. However, the degree of control that the academies exert over these languages does not render the latter controlled natural languages in the sense that the various kinds of "simple English" (e.g., Basic English, Simplified Technical English) or George Orwell's fictional Newspeak are. They instead remain natural languages to a considerable extent and are thus not formal languages such as Attempto Controlled English. They have a degree of standardization that allows them to function as standard languages (e.g., standard French). The English language has never had a formal regulator in any country.

In the dystopian novel Nineteen Eighty-Four (also published as 1984), by George Orwell, Newspeak is the fictional language of Oceania, a totalitarian superstate. To meet the ideological requirements of Ingsoc (English Socialism) in Oceania, the Party created Newspeak, which is a controlled language of simplified grammar and limited vocabulary designed to limit a person's ability for critical thinking. The Newspeak language thus limits the person's ability to articulate and communicate abstract concepts, such as personal identity, self-expression, and free will, which are thoughtcrimes, acts of personal independence that contradict the ideological orthodoxy of Ingsoc collectivism.

In the appendix to the novel, "The Principles of Newspeak", Orwell explains that Newspeak follows most rules of English grammar, yet is a language characterised by a continually diminishing vocabulary; complete thoughts are reduced to simple terms of simplistic meaning. The political contractions of Newspeak – Ingsoc (English Socialism), Minitrue (Ministry of Truth), Miniplenty (Ministry of Plenty) – are similar to Nazi and Soviet contractions in the 20th century, such as Gestapo (Geheime Staatspolizei), politburo (Political Bureau of the Central Committee of the Communist Party of the Soviet Union), Comintern (Communist International), kolkhoz (collective farm), and Komsomol (communist youth union). Newspeak contractions usually are syllabic abbreviations meant to conceal the speaker's ideology from the speaker and the listener.

Attempto Controlled English (ACE) is a controlled natural language, i.e. a subset of standard English with a restricted syntax and restricted semantics described by a small set of construction and interpretation rules. It has been under development at the University of Zurich since 1995. In 2013, ACE version 6.7 was announced.

ACE can serve as knowledge representation, specification, and query language, and is intended for professionals who want to use formal notations and formal methods, but may not be familiar with them. Though ACE appears perfectly natural—it can be read and understood by any speaker of English—it is in fact a formal language.