Sign Languages

Limited gesture systems or sign languages which are in use in a speech using community (in social groups, for working tasks) can be transformed into sign languages. Requirements for transformation imply that there is no restriction on one function and that the number of gestures can be enlarged.

Circumstances which enable the emergence of sign languages are:

• alternatives to spoken language (custom, taboos)
• various languages come into contact suddenly (Indian Sign Language)
• speech is impossible (deafness - ASL American Sign Language or DGS Deutsche Gebärdensprache)

([Kendon 1983])