Language primarily used by deaf Americans, based on hand shape, location, movement and expression augmented by finger spelling. Adapted from French models in the nineteenth century (and completely distinct from British signing), sign language was also repressed by institutions which denigrated it as broken communication and sought to force the deaf to read lips and vocalize. Since the 1980s, it has been increasingly recognized as a complex language, the structure and expressiveness of which differs from English. It has become a sign of community for the deaf; hearing speakers study it as a recognized foreign language in universities and community programs. Estimates of signers in the US vary widely from several hundred thousand to 2 million.