There are perhaps three hundred sign languages in use around the world today. The number is not known with any confidence; new sign languages emerge frequently through creolization and de novo (and occasionally through language planning). In some countries, such as Sri Lanka and Tanzania, each school for the deaf may have a separate language, known only to its students and sometimes denied by the school; on the other hand, countries may share sign languages, although sometimes under different names (Croatian and Serbian, Indian and Pakistani). Deaf sign languages also arise outside educational institutions, especially in village communities with high levels of congenital deafness, but there are significant sign languages developed for the hearing as well, such as the speech-taboo languages used in aboriginal Australia. Scholars are doing field surveys to identify the world's sign languages. The following list is grouped into three sections : Deaf sign languages, which are the preferred languages of Deaf communities around the world; these include village sign languages, shared with the hearing community, and Deaf-community sign languages Auxiliary sign languages, which are not native languages but sign systems of varying complexity, used alongside spoken languages. Simple gestures are not included, as they do not constitute language. Signed modes of spoken languages, also known as manually coded languages, which are bridges between signed and spoken languages The list of deaf sign languages is sorted regionally and alphabetically, and such groupings should not be taken to imply any genetic relationships between these languages (see List of language families). Sign language list Contemporary deaf sign languages Africa There are at least 25 sign languages in Africa, according to researcher Nobutaka Kamei. Some have distributions that are completely independent of those of African spoken languages. At least 13 foreign sign languages, mainly from Europe and America, have been introduced to at least 27 African nations; some of the 23 sign languages documented by Kamei have originated with or been influenced by them. Americas Asia-Pacific Europe Middle East Historical deaf sign languages Martha's Vineyard Sign Language Old French Sign Language – ancestral to the French family Old Kent Sign Language Auxiliary sign languages Baby Sign – using signs to assist early language development in young children. Contact Sign – a pidgin or contact language between a spoken language and a sign language, e.g. Pidgin Sign English (PSE). Curwin Hand Signs – a technique which allows musical notes to be