[Timwi]

I can't speak for others, but for me it's not a matter of dividing people in the way you describe. It's more about deciding who my audience is. If I talk to someone about my latest programming project, the conversation is completely different if it's someone who has never done programming before, versus someone who also does programming, versus someone who uses the same technologies as I do.

A website that requires the user to write HTML code targets an audience that knows HTML. That's really all there is to it. But knowledge of HTML correlates extremely strongly with knowledge of CSS and JavaScript and a couple other internet basics, so it's not labeled “people who know HTML”, it's labeled “tech people”.