While most people would assume all deaf people communicate in one formal language, there are actually many different types of sign language that usually tell where someone is from!
For example, while there is a standard American sign language, there is something known as a “village sign language” that is particular to a certain area.
Where there is a large deaf community, natural signs develop that those who are able to hear also use to communicate with their deaf family or friends. These particular signs are localized and become so engrained they eventually become synonymous with the region or village.
The best example of this is Martha’s Vineyard Sign Language, with is different from American Sign Language and is detectable by deaf people almost immediately!
Also, those who are not formally educated often have a hybrid form of sign language in which certain areas incorporate their own signs. All of this results in “accents” which are extremely similar to spoken languages!