Scientists have only recently begun to show interest in signing as language; the common assumption was simply that sign language was a kind of substitute for the spoken word, using the hands to form letters and words. But now linguists have come to realize the range of sign language, both structurally and grammatically, and to understand that sign language offers all the possibilities of spoken language: rich vocabulary, rhetorical expression, metaphor, word-play, puns, and poetry are all within the grasp of the Deaf and hard-of-hearing who use sign language for everyday communication. (14 minutes)