Shafallah Center for Persons with Disabilities adopts the notion that language is a behavior that can be learned and can be replaced in the absence of other reinforcement behaviors, or alternatives such as picture (PECS), descriptive signs or speech generating devices, Augmentative and alternative communication (AAC) describes multiple ways to communicate that can supplement or compensate (either temporarily or permanently) for the impairment and disability patterns of individuals with severe expressive communication disorders.