According to the Autism Society of America (ASA),
"Autism is a neurobiological condition that affects a person's ability to communicate and interact with others. It is a Pervasive Developmental Disorder (PDD) that affects boys four times more often than girls, and it is a "spectrum disorder" that affects individuals differently and to varying degrees of severity. Other PDDs include Asperger's Disorder, Rett's Disorder, Childhood Disintegrative Disorder and PDD-NOS (Not Otherwise Specified). Although each individual with autism improves in functioning over time, unfortunately, children do not "grow" out of autism. It is a lifelong disability."