Foreword

Explaining what HTML5 is can be a very daunting task. I’ve been doing this since its inception, and I’m still amazed by how many myths abound and how much confusion there is on the topic. With HTML5, we rebooted web development. The world of HTML4 and the nonstarter XHTML stranded those who wanted to use the web as a platform for applications. HTML4 was meant for linked documents, and XHTML was far too strict for its own good and lacked real support in browsers.

HTML5 started with a clean slate. We analyzed what was used on the web and added a lot of features we didn’t have before, like Canvas for creating visuals on the fly or accessing images and videos on a pixel level, native audio and video without the need for plug-ins, and forms that validate in the browser without our having to write extra JavaScript. We also started muddying the waters by merging HTML and JavaScript functionality—a lot of HTML5 won’t do anything without accessing the elements via a JavaScript API. This confuses many people. We moved on from a document-based web, and in that process we needed more technical expertise. And this meant we needed to rethink a few of our “best practices,” which can annoy people so that they spread nasty rumors about the viability of HTML5 as a choice for professional development.