Sign language Deaf 5 Means of communication 4 Study and teaching 3 Animal communication 2 Signs and symbols 2 Aboriginal Australians 1 Apes 1 Behavior 1 Children 1 Chimpanzees 1 Computers 1 Congresses 1 Deaf children 1 Dictionaries 1 Education 1 Gorilla 1 Human-animal communication 1 Indian sign language 1 Interpreters for the deaf 1 Koko (Gorilla) 1 Language 1 Outlines, syllabi, etc 1 Outlines, syllabi,etc 1 Psychology 1 Symbolism in communication 1 Terminology 1 Translating and interpreting 1