American Sign Language (ASL) is a natural language that serves as the predominant sign language of deaf communities in the United States and most of Anglophone Canada. ASL is a complete and organized visual language that is expressed by employing both manual and nonmanual features. Besides North America, dialects of ASL and ASL-based creoles are used in many countries around the world, including much of West Africa and parts of Southeast Asia. ASL is also widely learned as a second language, serving as a lingua franca. ASL is most closely related to French Sign Language (LSF). It has been proposed that ASL is a creole language of LSF, although ASL shows features atypical of creole languages, such as agglutinative morphology.
A sign language interpreter at a presentation
American Sign Language Convention of March 2008 in Austin, Texas
Phonemic handshape /2/ [+ closed thumb]
Phonemic handshape /3/ [− closed thumb]
Sign languages are languages that use the visual-manual modality to convey meaning, instead of spoken words. Sign languages are expressed through manual articulation in combination with non-manual markers. Sign languages are full-fledged natural languages with their own grammar and lexicon. Sign languages are not universal and are usually not mutually intelligible, although there are also similarities among different sign languages.
Two men and a woman signing American Sign Language (2008)
Juan Pablo Bonet, Reducción de las letras y arte para enseñar a hablar a los mudos ("Reduction of letters and art for teaching mute people to speak") (Madrid, 1620)
Chirogram from Chirologia, 1644
Sign language relief sculpture on a stone wall: "Life is beautiful, be happy and love each other", by Czech sculptor Zuzana Čížková on Holečkova Street in Prague-Smíchov, by a school for the deaf