Autism is a type of mental and developmental retardation. Its characteristic symptoms include: problems with language skills, problems with creativity, problems with communication, and problems with expressing emotion. Tic behaviors are common. Severe cases also include dysfunction in neuro-motor mechanics, and stereotyped movements.
Contrary to popular belief (as is seen in films such as Cube or Mercury Rising) autism does not imbue the person with the ability to do huge calculations, solve puzzles, or make them savant-like with some sort of specific skill. Savant syndrome in autistic people is actually extremely rare. Kim Peek (the man used as the basis for the central character in the movie Rainman) is one example of an autistic savant.
But Retardation is Politically Incorrect
Since not all conditions of autism relate to motor disabillities. They are only consistant of a syndrome that is part of a wide spectrum.
The Spectrum is the variant of all-related neural disabillities linked to Aspersers: The subject can become genious in certain area's, while failing socially in many cases. In other more hopeful cases, the condition can be mild enough, only to have affect on behaviour.