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The "XHTML vs. HTML5" Lesson is part of the full, Introduction to HTML5 and CSS3 course featured in this preview video. Here's what you'd learn in this lesson:

Christopher Schmitt dives right into the issues XHTML actually delivered, despite having been touted as ‘the next great thing’. Validation was a primary problem with XHTML – in fact research showed that only 5% of sites were actually validating. The “pain” of XHTML was realized in its inability to be easily-manipulated by multiple users, rendering it obscure and unwieldy to maintain. Secondly, adoption was a problem with XHTML, which could be tied directly to the adoption rate of IE6. Another issue was the limited number of elements it offered - especially when dealing with large amounts of content. A look at microformats - little process templates created by Tantek Çelik. Get the book Microformats Made Simple, by Emily Lewis and visit http://microformats.org/ to get a good foundation. The BBC quit using microformats when closed-captioning would only expose underlying data instead of text (ie: long/lat location vs city name). Significant changes in the web –video, audio, etc. – continue to drive the need for functionality beyond what HTML was initially designed to do. In real life, aligning blueprints with reality is rarely feasible – usually, users dictate the function of the “object” and the web is no exception. A quote by Frank Lloyd Wright -“Take care of the luxuries and the necessities will take care of themselves” – is the essence of the approach to HTML5. They’re taking all that worked in HTML and building HTML5 with all the “luxuries” in its foundation - leaving XHTML behind. Christopher reviews the agenda for this talk and gives a rundown of his experience: Co-author of Interact with Web Standards, The HTML Cookbook and The CSS Cookbook.

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