American Sign Language

American Sign Language (ASL) is a natural language used primarily by Deaf communities in the United States and much of English-speaking Canada. It is a fully developed visual–gestural language employing both manual signs and non-manual features such as facial expression, body movement, and head position. ASL is also used in parts of West Africa, Southeast Asia, and among international Deaf communities, often functioning as a lingua franca. Although it coexists with English in North America, ASL is structurally distinct and should not be considered a signed form of English.

Linguistic Features

ASL signs consist of several phonemic components, including handshape, location, movement, orientation, and facial expression. These combine to create a rich and complex linguistic system capable of expressing abstract concepts, narrative detail, and grammatical relationships. Iconicity, the resemblance of form to meaning, plays a noticeable role in ASL, though the language is not restricted to iconic signs and operates according to its own grammatical conventions.
Loanwords from English are most often incorporated through fingerspelling, but ASL grammar differs significantly from English syntax. The language employs verbal agreement, aspect marking, and a productive classifier system in which specific handshapes represent classes of objects and their movement or interaction. ASL is frequently analysed as favouring a subject–verb–object word order, though alternative models emphasise its use of topic–comment structures and spatial grammar.

Classification and Language Relations

ASL emerged in the early nineteenth century at the American School for the Deaf (ASD) in Hartford, Connecticut, which brought together children using diverse sign varieties. These included Old French Sign Language (LSF), several New England village sign languages, and numerous home sign systems. The resulting contact situation produced a new, distinct sign language that developed its own grammar and vocabulary.
ASL shares approximately half of its modern vocabulary with early French Sign Language, reflecting its initial influence, but the percentage is far below the threshold typically used to classify dialects of the same language. Observers noted that Laurent Clerc, who brought LSF to the United States, often adopted signs used by his students rather than imposing French forms. Consequently, modern ASL is not mutually intelligible with LSF, nor with British Sign Language (BSL) or Auslan, despite all emerging within English-speaking environments. Similarities among ASL, BSL, and Auslan are better explained by the high degree of iconicity typical of signed languages rather than by genealogical relationship.
Some scholars have proposed that ASL originated as a creole language combining LSF and local sign systems. However, modern ASL does not consistently exhibit structural features associated with creoles, such as strictly isolating morphology. Its agglutinative structure, facilitated by the visual–gestural modality, supports the view that it either ceased being creole-like over time or never fully conformed to creole typology.

Growth, Use, and Cultural Significance

ASL is widely used as a first language by Deaf individuals and by many hearing people who belong to Deaf families or work within Deaf communities. Although precise demographic data are unavailable, estimates suggest that 250,000 to 500,000 people in the United States and Canada use ASL.
The cultural practices associated with ASL contribute to a distinct Deaf culture, characterised by shared norms regarding eye contact, facial expression, and the use of signing space. These cultural features reflect the communicative functions of ASL and reinforce group identity within Deaf communities.
Growing public interest in ASL has led to its increasing acceptance in educational institutions. Many secondary schools and universities now recognise ASL as fulfilling foreign language requirements, and several states require its acceptance for academic credit. Its rising prominence reflects broader recognition of signed languages as legitimate linguistic systems rather than auxiliary forms of communication.

Historical Development

Before the establishment of ASL, a variety of sign languages were already in use across North America. Indigenous groups, including Plains communities, employed Plains Indian Sign Language for intertribal communication. Home sign systems also developed within hearing families who had deaf children, often achieving considerable complexity.
Three notable village sign languages existed in nineteenth-century New England: Martha’s Vineyard Sign Language (MVSL), Henniker Sign Language in New Hampshire, and the Sandy River Valley Sign Language in Maine. MVSL was especially influential due to the high incidence of hereditary deafness on Martha’s Vineyard. Signing was common among both deaf and hearing residents, and children from these communities brought MVSL into the ASD environment.
The American School for the Deaf opened in 1817 under the leadership of Thomas Hopkins Gallaudet and with instruction provided by Laurent Clerc, who had trained at the Parisian institution founded by Charles-Michel de l’Épée. Gallaudet’s exposure to European deaf education convinced him to adopt methods involving sign language, and the French influence helped shape early ASL. Over time, further schools for the deaf adopted ASL, and Deaf associations played a major role in spreading the language across the United States.

Language Contact and Social Context

The formation of ASL illustrates how sign languages can emerge rapidly through contact and community formation. As students from different signing backgrounds interacted, a shared language developed and stabilised across generations. Deaf community organisations, such as the National Association of the Deaf and fraternal societies, provided a social network that sustained and standardised ASL across wide geographic areas.
During periods when oralism dominated deaf education, ASL faced institutional suppression, yet it persisted through use in Deaf homes and community networks. The resilience of ASL in the face of such policies underscores its cultural and social importance to Deaf identity.