Autism is a developmental disorder characterized by problems such as difficulties in analysing and interacting with people.
Autistic people have no interest in catching attention and cannot understand excitement as others do. So they end up laughing without any reason and would show their excitement in a special way.
The mind of autistic people is much like a puzzle, in which the person tries to complete the puzzle.
The efforts made by the autism support groups for improving the life of these people is applaudable; but still there has been no certified cure for the disorder.