Contrary to popular belief, sign language is not international.
Fingerspelling is used in sign languages, mostly for proper names, although it is merely one tool among many. In the past, the use of fingerspelling in sign languages was taken as one of the evidences that sign languages are just broken or simplified versions of spoken languages. To say that a signed language is not a true language because it uses fingerspelling is akin to saying that English is not a true language because it contains onomatopoeicwords. Fingerspelling can sometimes be a source of new signs. Signs which have evolved from fingerspelling are called lexicalized signs.
On the whole, sign languages are independent of spoken languages and they follow their own developmental paths. For example, British Sign Languageand American Sign Language are different and mutually unintelligible (other than iconic signs), even though the hearing people of Britain and America share the same spoken language.
Sign languages are not often written; most deaf people who use sign language read and write the spoken language of their country.
There are also a large number of less formally organised but still widely understood gesticulations and mimes.
These range from expressing universal needs such as pointing to the mouth or rubbing the stomach to indicate a desire for food, to more insultinggestures such as the one-finger salute. It should be noted that not only do these not form a coherent language but their meaning may vary from culture to culture.
Contemporary Local Sign Languages
Contemporary Pan-National Sign Languages