ASL is really a language. It is not English conveyed into signs, nor is it a manual code for English. There is not just one universal sign language for deaf people worldwide. Since ASL has a grammatical structure, just as does any language, which makes it a distinct language. It seperates itself from others, however, in that it is spoken visually, not audibly as others are, with precise words and movements. ASL can convey ideas of all sizes, just as speakers of English can. Also, since ASL is a language, it is only spoken by a certain region of the world, thus there are many dialects. Deaf people worldwide use several different sign languages.
ASL was developed by the American Deaf in 1817, for communication purposes. Laurent Clerc and Thomas H. Gallaudet established the first school for the deaf in the U.S. From there on, the schools spread throughout America and Canada. The language passed through posterity residentially, though school and dormitory life. At times when signing was not permitted in the classroom, the parents, students, and teachers secretly used it. Now, ASL is used by a half million people in America and Canada.
People have been discouraged from using ASL since the late 1800's. Educators have insisted that deaf children learn to speak English, as they deem deaf people can fit into society only by lipreading and speech. Some educators have even gone so far as to tie down a person's hands to prevent them from signing. Despite the attempts to phase out ASL, the deaf community still prefers ASL.