HTML 5 <video> tag vs Flash video. What are the pros and cons?

Question

IMPORTANT UPDATE

This question was made over 9 years ago. It made sense then, it doesn\'t make it now. Flash is hard on its way out; sup

Answer 1

Flash is a real headache on non-Windows platforms. Not only is it slow and inefficient (as someone else pointed out), but it isn't very stable, either. As we learned at the most recent Apple WWDC, "browser plugins" (read: Flash) account for the majority of all application crashes across all of Mac OS X (and by "majority", I mean some absurdly high number like 80% or something, can't remember the exact figure offhand). This is such a problem on Mac OS X that for Snow Leopard, Apple has re-engineered Safari so that Flash runs, not just sandboxed, but in fact as an entirely separate process, so that when (not if) Flash crashes, Safari as a whole remains unaffected.

The instability of Flash on OS X, coupled with its poor performance, is why...

• ...Flash is not now, nor unlikely to be soon, available for the iPhone. I disagree with the premise that people don't want to watch video on their mobile devices -- this is why Apple made a special arrangement for YouTube to serve their content in h.264 for the purposes of allowing it to play on the iPhone. I, for one, happily paid the $10 for MLB 2009 exactly because I could watch video on my iPhone, and if they made every game available for live viewing, I'd pay much much more.
• ...so many Mac OS X users (like me) are installing Flash blockers for their browsers. By my choice, Flash content no longer even loads in my browser without my explicit permission. Since installing it, my CPU usage has dropped considerably, and my browser crashes have basically gone away. This is great news for me, of course, but it's bad news for any advertisers hoping to serve me Flash-based ads.

As far as users having to know anything about codecs is concerned, you can avoid this issue and serve them the appropriate codec (including Flash, if their browser doesn't support OGG or h.264) by using the simple non-Javascript html code found in this article.