By now you’ve probably heard of HTML5, the platform that every browser maker from Microsoft to Mozilla to Google can’t stop heralding as the savior of the Internet. Buzzwords aside, developers are excited about HTML5 because it creates a more elegant online experience, enabling users to enjoy the the best aspects of the web–audio, video, multimedia–without having to install external applications like Adobe Flash. In other words, HTML5 allows us to experience the Internet natively, and escape what Mozilla VP of products Jay Sullivan calls “plug-in prison.”

Sullivan is gung-ho about HTML5, which has become a major selling point of Firefox 4, the browser’s latest iteration set launch in the coming weeks. That’s great news for Firefox’s 450 million users, but it’s not so positive for Adobe, which could see one of its premiere products become irrelevant. So is Flash going away?

“I think so in the long run,” Sullivan says. “A lot of it has to do with HTML5. With Firefox 4, Internet Explorer 9, and Chrome, to the extent that we provide functionality in enough browsers, then the developers will switch over to HTML5, especially in mobile, where you can’t have Flash popping up on every page just to do some little animation. The idea that you’d have to embed an entire instance of the Flash player just to play a 30 second audio clip? It’s crazy.”

Like Apple, which sparked a war with Adobe after it banned Flash from its iPad and iPhone devices, Sullivan sees HTML5 as a more viable option than Flash. In fact, Flash is responsible for more crashes on Firefox than any other plug-in, and the company went so far as to introduce crash protection (“Flash” protection?) in June to curb instabilities. “God forbid Flash were to crash,” Sullivan says with a smile, before explaining how Mozilla now isolates such errors.

“HTML5 is the longer-term answer,” Sullivan says. “We’re on that path now.”

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