All three of these mediums need a player to work, and all three mediums are either dead or dying. Just as CDs replaced tapes as a more efficient means of playing music, and digital files replaced CDs to do the same, HTML5 is making Flash obsolete. The HTML5 versus Flash debate has been a hot topic among Web developers for years – and even more so since Steve Jobs published his now infamous 2010 letter touting HTML5 as the future and Flash as “no longer necessary.” But whether you side with Flash or HTML5, there’s no denying that the implications of HTML5 on video and the Web are real. For online video, HTML5 offers two things Flash does not: mobile capabilities and semantic markup. The growth of mobile engagement; the rise of Interactive Video for entertainment, advertising and shopping; and HTML5’s open structure all combine to create the future of an HTML5-based Web, leaving Flash to eventually shuffle into its place in the Retired Tech Hall of Fame (make some room Windows XP, Palm Treo). Mobile killed the Flash star. Since HTML5’s introduction, mobile has been touted as one of the publishing language’s largest advantages. And since iOS and many Android devices don’t support Flash, Flash is bound to PCs – a market which, according to Gartner, saw a 10 percent decline in shipments in 2013 from 2012.According to IAB.net, nearly half of the U.S. population has a mobile phone with Internet access, and one in five page views on the Web happen on a mobile device.Those numbers will continue to grow each month, and companies making Flash-based Interactive Videos are missing out on a huge audience by not enabling their videos to run on mobile devices.Let’s take Bob Dylan’s fantastically entertaining “Like a Rolling Stone” Interactive Video that launched in November. Millions of PC viewers clicked with joy within the video’s TV-like interface. However, users trying to open the video on their phone or tablet had a less enjoyable experience: Android users got a video teaser and a message to experience the full video on their desktop computer, and the site directed iOS users to download an app – neither option allowing for playback on their phone or tablet’s Web browser.If one in five page views are happening on mobile, that’s one out of five people having to deal with a broken user experience when they go to the video site on a mobile device.Those in the advertising, shopping, and enterprise industries are also beginning to focus their attention on mobile’s importance, as well as on Flash’s limitations with online video. A recent open letter to advertisers by the Interactive Advertising Bureau – and signed by several major publishers and ad firms, including AOL, Conde Nast, Forbes, Google, The New York Times, Time Inc. and the Wall Street Journal – urges marketers to implement the HTML5 standard for their mobile ads so that they can run on different platforms. The letter states that to guarantee the paid ads “actually appear and look great on all screens,” ads should be developed in a mobile-compatible format.“And the one open, industry-standard, universal format for building mobile-ready creative is HTML5,” the letter says. In Sizmek’s annual Global Benchmark Report, “Breaking Boundaries: Engagement Gone Global,” the shift towards more mobile friendly formats using HTML5 is emphasized as one of the most important changes in digital advertising during 2013. The report, which reveals key trends in digital advertising from more than 913 billion ad impressions worldwide for 2013, says to “expect engagement rates for HTML5 to increase in 2014 as the industry adopts rigorous creative and publishing standards that ensure seamless multiscreen delivery.”Not only is the ability to play ads on all platforms crucial for major publishers, it’s also imperative that once the viewer clicks on the ad, they’re able to actually buy the product without any issue. This isn’t always the case, however, because Flash-based sites limit what can be done on mobile devices. However, that’s not stopping enterprise and game developers. In a recent report from Sencha, a provider of open-source Web application frameworks, more than 60 percent of business application developers have converted to HTML5 and hybrid development of their key projects, and more than 70 percent of HTML5/hybrid developers are using HTML5 more this year than last.Mobile video isn’t the only culprit In the gaming industry, HTML5-based games are on the rise. Holland-based Spil Games is just one publisher taking the HTML5 path. The company plans to publish more than 1,000 HTML5 games by the end of the year. Spil Games already has 5,000 Flash games published on the Web, but that’s 5,000 games in its library that won’t work on tablets or phones.According to Digital Buzz Blog, 32 percent of time spent on iOS and Android devices is spent playing games. With HTML5, developers can create games that can work on all devices. Just look at some of the awesome stuff Google created with its Google Chrome Experiments (all built in HTML5 and JavaScript using open Web technologies such as Canvas, WebGL and WebRTC).And the nail in the Flash coffin award goes to… SEO.While mobile is the most obvious advantage of HTML5 over Flash, there’s a feature that lies in semantic structure that’s just as important and especially powerful for Interactive Videos based on HTML5. Web crawlers and search engines can’t see inside of Flash, which is a completely closed container, and they’ll never be able to. Why does that matter? With the semantic structure of Interactive Video, you can build projects using HTML5 that have multiple interrelated pieces that Web crawlers know how to understand. But with Flash, you’re getting a black box that, when crawled, shows up as just a Flash video without any extra information.Let’s take a look at another recent interactive music video, the 24-hour-long, HTML5-based project for Pharrell Williams’ “Happy.” The video, which allows viewers to interact and jump between 24 hours worth of footage of happy dancers lip-synching to Pharrell’s song, is a beautiful example of the powerful and immersive projects you can create with HTML5. There’s a new dancer or group of dancers every four minutes, totaling 360 clips – 24 of which include Pharrell himself. In addition to Pharrell’s appearances, there are also cameos by the likes of Steve Carell, Jamie Foxx, Magic Johnson, Kelly Osborne and more. The video is really impressive, but it missed an opportunity by not building on a semantic structure. Had it been built correctly, each of the 360 videos would refer to that single Web page, making it possible for viewers to do things like search on Google for the clip of Jamie Foxx and his family. Without watching the entire video, you might not find these “Easter eggs” without knowing their exact time stamps.Building the video on a semantic structure would’ve allowed Web bots to crawl each distinctive video clip as its own page. The video could have title tags and all the information you’d expect from a standard Web page (H1 tags, meta info, etc.), which would allow bots to read the single video as 360 individual Web pages with discrete content, resulting in higher-ranking search results. Content creators who aren’t building HTML5 videos are already behind, and they’ll soon be left completely in the dust if they don’t implement the HTML5 Web publishing language soon. However, the good news for brands and content creators is that there are companies focused on delivering all the benefits of HTML5 without any of the technical challenge or complication.Those who still think Flash is the way to go for online video will likely be changing their tune in the near future as mobile usage continues to skyrocket and HTML5 gets closer to becoming the universal format for creating mobile-ready creative projects.