how are they classified?
Home sign, pidgin, creolization
Sign language
Sign languages may be classified by how they arise.

In non-signing communities, home sign is not a full language, but closer to a pidgin. Home sign is amorphous and generally idiosyncratic to a particular family, where a deaf child does not have contact with other deaf children and is not educated in sign. Such systems are not generally passed on from one generation to the next. Where they are passed on, creolization would be expected to occur, resulting in a full language. However, home sign may also be closer to full language in communities where the hearing population has a gestural mode of language; examples include various Australian Aboriginal sign languages and gestural systems across West Africa, such as Mofu-Gudur in Cameroon.
ways in which infants learn the meanings of new words Infants must be able to hear and play with sounds in their environment, and to break up various phonetic units to discover words and their related meanings. at what age do they start speaking? At one year how do they develop their oral languages? Perception of speech, observe the mouth movements of others , discriminate sound phonologically what will be their first choice of words? "No" and "dada" when does babbling occur? It begins between five and seven months of age what is manual babbling? It is when infants babble with their hands and grow up using sign language how does this occur in deaf infants? Manual babbles are characterized by repetitive movements that are confined to a limited area in front of the body similar to the sign-phonetic space used in sign languages what is vocabulary spurt? UNANSWERABLE when did the sign language develop? Fifth Century BC what is its relationship with spoken language? They  are independent of spoken languages and follow their own paths of development
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Sign language [SEP] Classification
Although sign languages have emerged naturally in deaf communities alongside or among spoken languages, they are unrelated to spoken languages and have different grammatical structures at their core. Sign languages may be classified by how they arise. In non-signing communities, home sign is not a full language, but closer to a pidgin. Home sign is amorphous and generally idiosyncratic to a particular family, where a deaf child does not have contact with other deaf children and is not educated in sign. Such systems are not generally passed on from one generation to the next. Where they are passed on, creolization would be expected to occur, resulting in a full language.