@Springiscomingsoon
You asked about being affected socially.
Generally not being able to pick up on any inferences and hints, literal interpretation, quite fixed thought-patterns. The social impairments of autism can be massive because autistic kids don't think in the same way that NT kids do.
To receive a diagnosis of ASD, the following criteria need to be met.
"Is it autism?
The characteristics of autism vary from one person to another, but in order for a diagnosis to be made, a person will usually be assessed as having had persistent difficulties with social communication and social interaction and restricted and repetitive patterns of behaviours, activities or interests since early childhood, to the extent that these "limit and impair everyday functioning
www.autism.org.uk/about/diagnosis/children.aspx
Communication, as you can see, is featured very highly in the diagnostic process.
Just to comment on a few of the things mentioned upthread,
Autism is a medically diagnosed condition, it's not some random thing someone peels off a jar of jam and sticks on your child, it's a rigorous time-consuming process usually carried out by several medical professionals. Paed, SLT, OT and Ed Psych.
No, everyone is not on the spectrum somewhere. To be diagnosed, you have to meet the above criteria, particularly the bit that says "to the extent that these "limit and impair everyday functioning"
People can have a few traits but that doesn't make them autistic.
A diagnosis can help in school, in FE or Uni and at work for reasonable adjustments. Help in schools should be needs-based but some schools won't implement above a certain level of help without a diagnosis and an EHCP.
Without a diagnosis, some kids with autism are treated as naughty all through school and their autistic behaviour is seen as disruptive and they are punished for it.
If someone is autistic, they are born with it, it's a lifelong condition. A diagnosis cannot make someone autistic, no diagnosis does not mean no autism.
High Functioning does not mean 'can easily pass for NT so has no problems with anything.'
Mild Autism just means other people don't see the struggle behind the scenes.
Autism is often accompanied by other conditions.