Why HTML5 focus so much on Javascript? [closed]

Question

I am learning HTML5. I see almost everything is linked to JS. Why is it so much JS focused than HTML/XHTML?

Answer 1

It's not per se. Javascript is just a very common thing in quality UI's these days. Designers and developers demand interaction on their interfaces that can in many cases only be accomplished via client-side interaction, which is what javascript gives you. Because HTML 5 is cutting edge, it's logical that quality UI guys with expertise in javascript would be flexing their muscle.

HTML5 is responding to many things such as video and tweening that used to require plugins like Flash and Javascript to accomplish. This will allow us to provide these "advanced" features more natively, improving usablity. You'll already see this in examples like YouTube's html5 video delivery, which is compatible with mobile browsers that don't support Flash.