Autism is a complex neurodevelopmental disability that typically appears during the first three years of life. It is the result of a neurological disorder that affects the functioning of the brain. No count has ever been made of exactly how many people have autism, though current estimates place the rate of autism spectrum disorders as high as 1 in 110 children. Autism is about four times more prevalent in boys than girls and knows no racial, ethnic or social boundaries. Family lifestyle and educational levels do not affect the chance of autism's occurrence.

Autism impacts the normal development of the brain in the areas of communication skills and social interaction. The disorder makes it difficult for children and adults with autism to communicate with others and understand verbal and non-verbal communication. In some cases, aggressive and/or self-injurious behavior may be present. Persons with autism typically exhibit repeated body movements (hand flapping, rocking), unusual responses to people, attachments to objects, and resistance to changes to routines. Individuals may also experience unusual sensitivity to sights, sounds, or other sensory inputs.