Sign languages utilize a combination of hand gestures, facial expressions, and body language to convey meaning.

Sign languages consist of both iconic signs, which have a visual resemblance to their meaning, and arbitrary signs, which do not have a direct visual connection to their meaning.

Sign languages have their own unique grammatical structures, encompassing sign grammar, sign syntax, and sign morphology.

Non-manual markers in sign languages serve various purposes, including indicating grammatical information, conveying emotions and attitudes, and emphasizing certain words or phrases.

The signing space is the area in front of the signer where signs are produced and perceived.

The handshape in a sign refers to the combination of hand configuration, hand position, and hand orientation.

Sign movement encompasses both hand movement and arm movement in the production of a sign.

The sign location, sign position, and sign placement all refer to the specific area in the signing space where a sign is produced.

Non-manual signals, non-manual markers, and non-manual components all refer to the facial expressions and body language that accompany signs in sign languages.

Sign language phonology encompasses the combination of hand gestures, facial expressions, and body language that make up the sound system of a sign language.

The sememe is the smallest unit of meaning in a sign language.

Sign formation, sign creation, and sign derivation all refer to the process of creating new signs in a sign language.

Sign modification, sign alteration, and sign transformation all refer to the process of changing the meaning of an existing sign in a sign language.

Sign borrowing, sign adaptation, and sign integration all refer to the process of borrowing signs from other sign languages or spoken languages.

Sign attrition, sign loss, and sign extinction all refer to the process of losing signs from a sign language.