YouTube drops Flash for HTML5 video as default ... How would this benefit the users .. what tangible impact users will have?

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First, the differences...Availability- Html5 standard and Webkit implementation is converging and growing.Scalability- It scales all the way from mobile to full power workstation.Portability- Possibility to develop cross-browser Html-like app, the extensive use of proprietary features in "so-called Html5"  apps today making cross-browser works non-trivial.http://www.sbp-romania.com/Articles/flash-vs-html5-analysis.aspxNext the benefits...- Availability especially for mobile and table users.

- Less pain, as it's seldom those apps with HTML5 crashes unlike in Flash based...it's quite common to see the flash runtime crashing.

- The future, technology is heading toward portability like tablets, mobile/smartphones or the so called internet of things gadgets... HTML5 is so lightweight comparable to Flash that most companies is adapting the technology giving the user more options/products to enjoy.

Well, As we all know, the programming and video space is constantly evolving I'm not the HTML5 writing expert as it's not my area of expertise. However, What I do know as a Motion graphics/Video content creator (H.264) it is suitable and very flexible in customisation along side CSS for web developers. Besides, It's a good shift from less secure and mobile battery draining Flash.  If you recall Apple got the stick for dropping support for Flash opting for HTML5, now suddenly other mobile device makers realising it also.

I 'think' we're likely to see more content in shape of Video's online alongside HTML5 for years to come.

 

Clodelio Delfino perfectly descriptive answered. In my words I would say. Addition to above lines (Clodelio Delfino)'s no need to download additional stuff to render the contents, secondly if you are doing to secure the browser or embedding the YouTube video into your app there are more options to easily secure your clients system as well.

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