Communal interaction designs are at the heart of what playhtml enables and requires in order to reach broad culture.
some fundamental questions
What is in the “frame” of the designed / laid out site, what is in another “layer” like something that slides out, another window, a modal, etc? how does someone understand where playhtml begins and where it ends? How to account for different spectrums of stateful vs. dynamicity fixed size (lamp) vs. dynamic (guestbook) how do you conceptualize space? in physical space, it’s clear what is here vs. there. in digital space, things can be shared or forked or replicated. how is the mental model intuitive and consistent for what is a shared space and what becomes a different shared space? think about video games and that consistency. ex: moving from one domain to another feels like a different space, you might be able to “take” an element from one website and move it to another and it would make sense, but if one person took an element from the website from the same website it would be weird if you didnt see them 
Interaction Design