The International Day of Sign Languages is a tribute to the millions of deaf people all over the world. According to the World Federation of the Deaf or WFD, there are 70 million of them and 80 percent of which are living in developing countries. Overall, the deaf population is said to be capable of using around 300 various sign languages. 
Sign languages are now as significant as spoken languages. Among them is an international sign language used for meetings and socializing. It is, to use an analogy, what English is to spoken language. 
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