Exploring the World of Sign Languages: A Global Perspective

Sign language (natural sign language)

A natural human language that uses the visual–gestural modality (hands, face, body, eyes) with its own grammar, vocabulary, and community of users, typically a Deaf community.

Visual–gestural modality

A way of expressing language using visible movements and positions of the body, hands, and face, perceived through the eyes, as in sign languages.

Spoken–auditory modality

A way of expressing language using the vocal tract to produce sound, perceived through the ears, as in spoken languages.

Home sign

A limited, family-specific gesture system created when a Deaf person has no access to a broader sign language community; useful but usually not a full language.

Baby sign

A small set of signs taught to hearing infants (often based on a sign language) to communicate basic needs before they can speak; not a full language.

Co-speech gesture

Spontaneous hand and body movements that accompany spoken language (like pointing or miming) but are not themselves a separate language.

Sign language (general idea)

A natural human language that uses the visual–manual modality (hands, face, body) instead of the vocal–auditory channel. Each sign language is tied to a community, not to a spoken language directly.

Sign languages (plural)

The many distinct visual–manual languages used by Deaf communities worldwide; they are not universal and are often mutually unintelligible.

Language family

A group of languages that share a common historical ancestor. In sign languages, examples include the French Sign lineage and the BANZSL family.

BANZSL

A sign language family that includes British Sign Language (BSL), Auslan (Australian Sign Language), and New Zealand Sign Language (NZSL).

French Sign Language (LSF) lineage

A group of sign languages historically influenced by LSF, including American Sign Language (ASL) and several sign languages in Francophone regions.

Indo‑Pakistani Sign Language (IPSL) cluster

A cluster of closely related sign varieties used across India, Pakistan, Bangladesh, and neighboring areas; sometimes treated as one language with strong regional variation.

Handshape

The configuration of the fingers and thumb in a sign (which are extended, bent, spread, etc.). A core phonological parameter in sign languages.

Location

Where a sign is produced in relation to the body or signing space (e.g., forehead, chin, chest, neutral space). Changing location can change meaning.

Movement

The path or type of motion in a sign (straight, circular, repeated, tapping, etc.). Movement often carries grammatical or lexical contrasts.

Orientation

The direction the palm and/or fingers face during a sign (up, down, toward signer, away, etc.). Orientation differences can distinguish signs.

Non-manual signals

Linguistic use of facial expressions, mouth shapes, eye gaze, head and body movements in sign languages. They mark grammar (questions, negation, topics) as well as affect.

Spatial reference (locus)

A specific location in signing space associated with a referent (person, object, idea). Later points or movements to that locus function like pronouns or agreement markers.

deaf (lowercase)

Refers primarily to the audiological condition of having little or no functional hearing, without necessarily implying a particular cultural or linguistic identity.

Deaf (uppercase)

Refers to a cultural and linguistic identity centered on the use of a sign language and participation in a Deaf community.

Audism

Discrimination or prejudice based on hearing status, often privileging hearing and spoken language over deaf people and signed languages.

Village signing community

A small community where both deaf and hearing people use a local sign language in daily life, often due to hereditary deafness and close social ties.

Intersectionality

An approach that examines how different aspects of identity (such as deafness, race, gender, disability, class) overlap to shape people’s experiences and access to power.

DeafBlind

Describes people with combined hearing and vision differences, many of whom use tactile or close-range sign languages and have distinct cultural practices.

Home sign

A gesture-based communication system developed by a Deaf person and their close hearing family when they have no access to an established sign language. Often systematic, but usually not a full language without a larger Deaf community.

Village sign language

A sign language that arises in a small community (often with high hereditary deafness) and is used by both Deaf and many hearing residents, independent of national sign languages.

BANZSL

A sign language family including British Sign Language (BSL), Australian Sign Language (Auslan), and New Zealand Sign Language (NZSL), which share a common historical origin.

Nicaraguan Sign Language (NSL)

A relatively new sign language that emerged in Nicaragua from the late 1970s onward, when Deaf children from different backgrounds came together in new schools and created a shared language.

Language contact

A situation in which users of different languages interact regularly, leading to borrowing, mixing, and sometimes the creation of new languages (as with ASL’s mix of LSF and local signs).

Oralism

An educational approach that emphasizes speech and lip-reading and historically discouraged or banned the use of sign languages in Deaf education.

CRPD (Convention on the Rights of Persons with Disabilities)

A UN human-rights treaty (in force since 2008) that requires states to ensure full and equal enjoyment of all human rights by persons with disabilities, explicitly recognizing sign languages as languages and stressing accessibility, education, and participation.

Legal recognition of a sign language

When a state formally acknowledges a sign language in its laws or constitution, often creating obligations to use, promote, and provide access to that language in areas like education, public services, and media.

Constitutional recognition

Recognition of a language (including a sign language) in a country’s constitution, usually giving it high symbolic status and forming a strong legal basis for demanding practical measures.

Accessibility (in the CRPD sense)

The obligation to remove barriers so that persons with disabilities can access the physical environment, transportation, information, communications (including sign languages), and services on an equal basis with others.

International Week of the Deaf (IWD)

An annual global event in the last full week of September, led by the World Federation of the Deaf, highlighting Deaf rights and sign languages through campaigns, events, and advocacy.

“No Human Rights Without Sign Language Rights”

A slogan used by Deaf advocates to stress that without access to sign languages, Deaf people cannot fully enjoy many other human rights, such as education, health, and political participation.

Oralist Education

An approach that focuses on teaching Deaf students to use spoken language and lipreading, often discouraging or banning sign language in the classroom.

Sign Bilingual Education

A model where a natural sign language is used as a primary language of instruction, and the majority written (and sometimes spoken) language is taught as a second language.

Total Communication

An approach that encourages using any and all modes of communication (speech, signs, gestures, pictures), but often lacks a clear, consistent language policy and can weaken full access to either language.

Mainstreaming with Interpreters

Placing Deaf students in regular schools with hearing peers and providing access through qualified sign language interpreters, captioning, or other accommodations.

Qualified Interpreter

A professional who is fluent in both the sign language and the spoken/written language, trained in interpreting (often with certification), and bound by a code of ethics.

Deaf Teachers

Educators who are Deaf themselves, often native signers and cultural role models, who can provide strong sign language input and understand Deaf students' experiences.

Sign language recognition

The process where AI systems detect and label signs (often as glosses) from video, usually within a specific sign language and domain.

Sign language translation

Using computational methods to translate between a sign language and a spoken/written language, often sign-to-text or text-to-avatar; currently limited in scope and accuracy.

Corpus (sign language corpus)

A large, organized collection of sign language video data with annotations (e.g., glosses, translations, metadata) used for research, dictionaries, and technology development.

International Sign (IS)

A contact variety used in international Deaf spaces (e.g., WFD, UN events). It is not a full replacement for national sign languages but helps cross-border communication.

Deaf leadership

Meaningful control and decision-making power held by Deaf people in projects that affect their languages and lives, from design to governance.

Context-aware translation

Translation systems that consider full sentences, discourse, and non-manual features (like facial expressions and body posture), not just isolated signs.

American Sign Language (ASL)

A natural sign language used primarily in the United States and parts of Canada; highly visible, widely taught in schools and universities, and commonly seen in media, though not declared by a single federal law as the official national sign language.

Indo-Pakistani Sign Language (IPSL)

A large sign language (often referred to locally as Indian Sign Language or Pakistan Sign Language) used by Deaf communities across parts of South Asia. It has millions of users but uneven legal recognition, educational support, and interpreter infrastructure across countries.

Azerbaijani Sign Language (AzSL)

The sign language used by Deaf communities in Azerbaijan, influenced historically by Russian Sign Language but with local features. As of 2026, it is under-recognized, under-documented, and lacks strong formal status in national law.

World Federation of the Deaf (WFD)

A global organization founded in 1951 that represents national Deaf associations, advocates for sign language rights and Deaf people’s human rights, and works closely with the United Nations, especially around the Convention on the Rights of Persons with Disabilities (CRPD).

International Week of the Deaf (IWD)

An annual global event, usually held in the last full week of September, organized by the WFD and national Deaf associations. It highlights Deaf culture, sign language rights, and advocacy through public events, campaigns, and community activities.

Under-recognized sign language

A sign language that is actively used by a community but has limited legal recognition, few educational resources, weak interpreter infrastructure, and little documentation or public visibility (e.g., Azerbaijani Sign Language).