American Sign Language
American Sign Language, also known as ASL or Ameslan, is a language in visual-manual modality. It is dominantly used by culturally Deaf people in the U.S. and speaking-English Canada. ASL is the 3rd or 4th most used language in the U.S.
The minister Thomas Hopkins Gallaudet visited the school for the deaf in Paris to learn about deaf education and teaching methods. There he met a brilliant young deaf teacher, Laurent Clerc in France. Eventually he convinced Clerc to return to America with him. On their journey by ship, Gallaudet taught Clerc English and Clerc taught Gallaudet French (sign language). They founded the first school for the deaf, American Asylum (now the American School for the Deaf) in Hartford, Connecticut.
The Old French Sign Language (OFSL) that Clerc brought to the U.S. was intermingled with the previous native sign languages. ASL has been evolved much since then.
In the 1960s, William Stokoe, a hearing English professor at Gallaudet University (formerly Gallaudet College), observed sign language used by the Gallaudet students. He studied and discovered that it had linguistic features (phonology, morphology, syntax, and all) like any spoken language. He researched and proclaimed that it is a language. His works were published in linguistics journals. Since the 1970s, a number of research and studies have widely grown.
There are many ASL courses provided in secondary and post-secondary schools, continuing education programs, and private classes in the U.S. today.