Many parents and professionals are concerned about using augmentative/alternative forms of communication (AAC) with young children because they are worried that the child will not talk if given the alternate form to use. Research is showing the opposite is true; using sign language, pictures, or written words can help the child to develop language skills and may even promote verbalizations.
Start early! If a child is not saying words by 12-18 months then it is time to use alternatives. If you need a place to begin, read the booklet Teaching Language, Literacy, and Communication.
Three components of communication:
Content is the meaning of the message. It is also called semantics.
Form is the structural aspect that includes attaching some symbol to the meaning. The symbol can include the spoken word, a picture, or a sign. The form/symbol is effective as long as the communicator and listener both agree on the meaning. Another part of form is the length and word order that includes syntax.
Use is the purpose, function, or reason for the communication. It includes pragmatics and social communication.