Sign language has been around for a long time. In fact deaf people have been using their hands to communicate for centuries.
Sign languages usually do not have any linguistic relation to the spoken languages of the countries they come from. The correlation between sign and spoken languages is very complex and varies depending on the country more than the spoken language. For example, the US, Canada, UK, Australia and New Zealand all have English as their dominant language, but American Sign Language, used in the US and most parts of Canada, is derived from French Sign Language. British, Australian and New Zealand have a different dialect.
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