I experienced significant social delays when I was growing up due to a variety of issues with non-verbal communication. I had a tough time understanding the structure of conversation; I couldn’t quite grasp all of the codes and unwritten rules that accompany an interaction. As a result, I wasn’t able to successfully begin making friendships until high school. (It’s worth noting that Asperger’s Syndrome did not yet exist as a diagnosis when I was growing up; the delays could have been shortened with a diagnosis and proper guidance.)
It was only when I finally made those friendships that I began to understand some of the reasons my social life had been difficult. Having a peer group meant that, for the first time, I was able to compare shared experiences. And in that sharing (which involved hanging out, talking, exchanging thoughts) it became apparent that my mind was processing information in a different way.
What I learned from that insight: I was not only struggling with social pragmatics (the structure and unwritten rules of conversation). Creating friendships was also difficult as a result of perceptual differences. Differences I had never noticed until I began to converse more openly with others.
I can think of one example that hopefully helps clarify what I mean.