People on the autism spectrum may be verbal or non-verbal, brilliant or mentally challenged, passive or aggressive, physically healthy or physically ill. They may have "savant" skills - or not. In fact, people with autism spectrum diagnoses seem to have very little in common.
So what do people on the autism spectrum really have in common?

This is what every person with autism as in common -
1. Qualitative impairment in social interaction.
2. Qualitative impairments in communication
3. Restricted repetitive and stereotyped patterns of behavior.
Or in other words – they have autism.
My first guess is they’re all people.
Easy answer; autism was independently and nearly simultaneously coined by both Kanner and Asperger on opposite sides of the Atlantic from the Greek “auto” for “self”. What we have in common is incredible self-absorption or selfishness. Not until we people on the autism spectrum reach a point in each of our lives of maturity and education where we can logically learn and understand that the large motive objects around us are people and that they have emotions and feelings and do not share our perspective can we even begin to truly communicate with these objects. Selfishness is our commonality, how long it takes to realize we are not the center of the universe is our defining difference within the autism community. Some never learn.
A love of trains.
Also: autistic people can be BOTH “brilliant” AND “mentally challenged.”
This is what all autistic people have in common:
1. A profound lack of affective contact.
2. Repetitive, ritualistic behaviour, which must be of an elaborate kind.
Oh wait. This is not 1960? Never mind. My bad.
The word “autistic” first turns up in the medical literature in 1912. From Grinker (Unstrange Minds, 2008):
The citation is:
Freud, Sigmund. 1921. “Introduction to J.Varendonck’s The Psychology of Day-Dreams.” Standard Edition, 18: 271. James Strachey, ed. London: Hogarth.
Most love the TV show Wheel of Fortune. That is true, but seriously:
Most people with autism can be noticed visually in a crowd because there is likely one form or another of a self-stimulatory behavior happening to a greater or lessor degree. Whether it is full blown rocking, spinning, shaking string in front of face, picking skin, nails, scabs, verbal stimming sounds and so forth or less obvious but noticable traits such as pacing, holding ears, red ears, uncommon facial expressions, to the trained eye, you could not miss those characteristics. They may all be slightly different in how they manifest, but most of the time, they look diffent than other people in diagnostic groups.
Recently I collected photos sent to me by many adults with autism (across the spectrum) and I also went searching through many sites that host photos of people with autism. The majority of the time, you will see a certain quirky look, that I think can be described as some form of self-stimulatory behavior. Of course there are always exceptions, but it is a noticable common denominator.
Karen Kaye-Beall, director
Foundation for Autism Support and Training
Autistic persons share hallmark traits, but to get a real good view of what a non verbal severely autistic person has to deal with I would suggest going to YOU TUBE and searching under, “autism and self-injurious behavior” and see just how severe autism can be and just how critical it is we find help for these severe types…..there are families out there dealing with such severe cases that they have no time to make themselves or their children’s needs known…they are just trying to survive the moments that crash down on them daily….truly sad…we don’t see this face of autism very often and these poor parents and children are the most needy of all autistics….we must speak up for them!