Sign languages are natural languages that arise independently among deaf communities and, with rare exceptions such as the deliberately documented village sign languages, are not genetically related to the spoken languages of the hearing populations that surround them. A national sign language is typically classified into one of a small number of sign language families defined by documented historical descent, French Sign Language's family, British Sign Language's family, German Sign Language's family and so on, rather than by the spoken language of the country where it is used. This group holds every Eurasian Language Families member whose sourced description identifies it as a sign language or a sign language family, collecting them into one place rather than leaving them scattered under whichever geographic or typological label their entry happened to carry.