Crux of the issue right here: I think it stems back to the decision by iOS to ban Flash. iOS friendly web pages needed to use HTML5 instead of flash, so the te

Crux of the issue right here: I think it stems back to the decision by iOS to ban Flash. iOS friendly web pages needed to use HTML5 instead of flash, so the term “HTML5” came to represent everything that came along with mobile friendly websites. That includes responsive design, and animations that run smoothly without a lot of power. Both those things are in the domain of CSS3, not HTML5.