CHAPTER 1 OVERVIEW OF HTML5
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I authored my first home page back in 1995. At the time, a ‘home page’ was something you created to talk
about yourself. It usually consisted of badly scanned pictures,
<blink> tags, information about where you
lived and what you were reading, and which computer-related project you were currently working on.
Myself and most of my fellow ‘World Wide Web developers’ were attending or employed by universities.
At the time, HTML was primitive and tools were unavailable. Web applications hardly existed, other than a
few primitive text-processing scripts. Pages were coded by hand using your favorite text editor. They were
updated every few weeks or months, if ever.
We’ve come a long way in fifteen years.
Today, it isn’t uncommon for users to update their online profiles many times a day. This type of
interaction wouldn’t have been possible if not for the steady, lurching advances in online tools that built on
each previous generation.
Keep this in mind as you read this book. The examples we show here may seem simplistic at times, but
the potential is limitless. Those of us who first used
<img> tags in the mid-1990s probably had no idea that
within ten years, many people would be storing and editing their photos online, but we should have
predicted it.
We hope the examples we present in this book will inspire you beyond the basics and to create the new
foundation of the Web for the next decade.”
The Myth of 2022 and Why It Doesn’t Matter
The HTML5 specification that we see today has been published as a working draft—it is not yet final. So
when does it get cast in stone? Here are the key dates that you need to know. The first is 2012, which is
the target date for the candidate recommendation. The second date is 2022, which is the proposed
recommendation. Wait! Not so fast! Don’t close this book to set it aside for ten years before you consider
what these two dates actually mean.
The first and nearest date is arguably the most important one, because once we reach that stage,
HTML5 will be complete. That’s just around the corner. The significance of the proposed
recommendation (which we can all agree is a bit distant) is that there will then be two interoperable
implementations. In other words, two browsers equipped with completely interoperable
implementations of the entire specifications—a lofty goal that actually makes the 2022 deadline seem
ambitious. After all, we haven’t even achieved that in HTML4 and only recently for CSS2!
What is important, right now, is that browser vendors are actively adding support for many very cool
new features, and some of those are already in the Final Call for comments phase. Depending on your
audience, you can start using many of these features today. Sure, any number of minor changes will
need to be made down the road, but that’s a small price to pay for enjoying the benefits of living on the
cutting edge. Of course, if your audience uses Internet Explorer 6.0, many of the new features won’t work
and will require emulation—but that’s still not a good reason to dismiss HTML5. After all, those users,
too, will eventually be jumping to a later version. Many of them will probably move to Internet Explorer
9.0 right away, and that version of IE supports many more HTML5 features. In practice, the combination
of new browsers and improving emulation techniques means you can use many HTML5 features today
or in the very near future.
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