HTML5 Please is an instructional website by Paul Irish, Divya Manian, Jake Verbaten, and various other developers on GitHub. The layout of the site provides visual displays on which practices should be used in today's HTML standards. Easy to follow labels such as use, caution, and avoid make following this guide a walk in the grocery aisle. There's a search bar to cross-reference any questionable html tags. These generous developers include a list that showcases where this information will and will not be valid. Finally, HTML5 Please is one of many sites created by these developers. HTML5 Boilerplate, CSS3 Please, and Modernizr.

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