Autism is one of the mental, emotional, and behavior disorders that appears in early childhood.
Autism, or autistic disorder, almost always develops within the first 3 years of a child's life. Children and adolescents with autism cannot interact normally with other people. Autism thus affects many aspects of their development. The symptoms of autism range from mild to severe. Although symptoms of autistic disorder sometimes can be seen in early infancy, the condition can appear after months of normal development.