Sign language, based on sight instead of sounds, is a type of language that uses hand movements, facial expressions and body language to communicate. It is used mainly by the deaf and people who can hear but cannot speak. But it is also used by some people without any hearing problems, most often families and relatives of the deaf, and interpreters (翻译员) who help build connections between the deaf and wider communities.
Sign language has several main visual (视觉的) parts that work together to express meanings. The first part is the shape made by the hands. The way of moving the body parts like hands also affects (影响) the meaning. The place where the sign is made and the direction the hands face are important, too.
Many people think sign language is universal(通用的), however, sign languages, like spoken languages, develop naturally out of groups of people; region(地区) and culture play a large role in the development. Therefore, sign languages differ from place to place. Take British Sign Language (BSL) and American Sign Language (ASL) for example --the sign languages used by the deaf in Britain and America are very different. Although the hearing people from the UK and the US perfectly understand one another, deaf persons from the UK and those from the US cannot communicate as fluently as normal people from the two countries.
Chinese Sign Language (CSL) has been developing mostly since the late 1950s and its signs are like written Chinese characters. Schools and workshops for the deaf in China help spread CSL. The Chinese National Association of the Deaf (CNAD) helps improve the quality of living for the deaf in China, promote the deaf community, and encourage the education of deaf people using sign language.
