This is a peculiar question to ask anyone who isn't into "Street Photography"...but what is it...I mean, street photography? To me it's a answer that I initially thought was an easy one until I tried to answer it.
Is it people in an environment where the image produced holds the viewers attention longer than a passing glance?
Or even more detailed - where a person sees an image where they exhale a short burst of air through their nose...not a laugh or a snort, just a recognition of a situation in a period of time?
It can be when a sequence of events leads to an image where you think "You couldn't make it up" - almost like spotting a rare bird or witnessing an unusual sporting event...you can say you were there.
But on the other hand the juxtaposition of people with their environment suits well. Just in a position that holds the attention but nothing startling stands out...it's just a situation. But then you just take a photograph just because it's an interesting composition and the people just add to the randomness and create a pleasing effect.
To try to answer the initial question - it's probably a lot of things to a lot of people but the interesting fact is that it is just that - varying and diverse. Rather like the people that feature in the images.