Autism is one of a group of neurodevelopmental disorders known as pervasive developmental disorders, which are characterized by impaired communication, impaired social interaction, and restricted, repetitive and stereotyped patterns of behaviors or interests. Autism spectrum disorders (ASDs) are used to describe three of the five pervasive developmental disorders, including autistic disorder, Asperger disorder, and a third category that includes pervasive developmental disorders that do not fit into the classic descriptions of developmental disorders.