Many countries have a language policy designed to favor or discourage the use of a particular language or set of languages. Although nations historically have used language policies most often to promote one official language at the expense of others, many countries now have policies designed to protect and promote
regional and ethnic languages whose viability is threatened. Indeed, whilst the existence of linguistic minorities within their jurisdiction has often been considered to be a potential threat to internal cohesion, States also understand that providing language rights to minorities may be more in their long term interest, as a means of gaining citizens' trust in the central government.
Language policy is what a government does either officially through legislation, court decisions or policy to determine how languages are used, cultivate language skills needed to meet national priorities or to establish the rights of individuals or groups to use and maintain languages. The scope of language policy varies in practice from State to State. This may be explained by the fact that language policy is often based on contingent historical reasons. Likewise, States also differ as to the degree of explicitness with which they implement a given language policy. The French Toubon law is a good example of explicit language policy. The same may be said for the Charter of the French Language in Quebec.
The preservation of cultural and linguistic diversity in today's world is a major concern to many scientists, artists, writers, politicians, leaders of linguistic communities, and defenders of linguistic human rights. More than half of the 6000 languages currently spoken in the world are estimated to be in danger of disappearing during the 21st century. Many factors affect the existence and usage of any given human language, including the size of the native speaking population, its use in formal communication, and the geographical dispersion and the socio-economic weight of its speakers. National language policies can either mitigate or exacerbate the effects of some of these factors.
For example, according to Ghil'ad Zuckermann, "Native tongue title and language rights should be promoted. The government ought to define Aboriginal and Torres Strait Islander vernaculars as official languages of Australia. We must change the linguistic landscape of Whyalla and elsewhere. Signs should be in both English and the local indigenous language. We ought to acknowledge intellectual property of indigenous knowledge including language, music and dance."
There are many ways in which language policies can be categorized. It was elaborated by Université LavalsociolinguistJacques Leclerc for the French-language Web site L'aménagement linguistique dans le monde put on line by the CIRAL in 1999. The collecting, translating and classifying of language policies started in 1988 and culminated in the publishing of Recueil des législations linguistiques dans le monde (vol. I to VI) at Presses de l'Université Laval in 1994. The work, containing some 470 language laws, and the research leading to publication, were subsidised by the Office québécois de la langue française. In April 2008, the Web site presented the linguistic portrait and language policies in 354 States or autonomous territories in 194 recognised countries.