Charles A. Ferguson's concept of "diglossia" (1959, 1964) is used in analyzing sign language. As in Haitian Creole or Swiss German, "two or more varieties" of sign language are "used by the same speakers under different conditions"--these are here called "High" (H) sign language and "Low" (L) sign language. H sign language is formally taught…

The study of pidgin and creole languages, usually emphasizing oral language codes, offers insights into language, especially as an observably dynamic phenomenon. However, channel is highly influential on the surface form of the language code. Pidgin sign language codes, not dependent on oral language codes, can serve as an ideal forum for the…