(Originally posted 2011–04–20.)
William Gibson’s “The future is already here — it’s just not very evenly distributed” applies very well to HTML5. It’s even more true of CSS3. Despite that (or maybe because of it) it’s a good time to dive into HTML5 – before everyone else does. 🙂
So, a few months ago I bought, read and inwardly digested 🙂 Mark Pilgrim’s HTML5 Up and Running, published by O’Reilly in August 2010. I have a rule of thumb: If a topic is covered by an O’Reilly book it’s probably ready for prime time. If it’s in “For Dummies” it’s probably too late. (With apologies to other similarly fine publishers and, of course, to the publishers of “For Dummies”.) It’s a glib rule but it’s mine. 🙂
So how does this rule of thumb work out for HTML5? Well, if you make a “poor choice” of browser then not very well. “Poor choice” is in quotes because:
No one browser fully implements HTML5.
It’s not just about which browser but about which level.
You might be happy with one browser’s implementation but not another’s.
There’s a degree of ambiguity, development of the state of the art, etc about HTML5 itself. I’d characterise it as a (slowly) moving target.
And note that this book is from last year. So things will have changed. But:
- It goes to great pains to describe the support by each browser.
- It makes the point in doing so that browser support is variable and you soon get the drift as to what each browser’s maker’s attitude is to HTML5.
Having been around a bit I know something about technology adoption: 25 years ago it would take at least 18 months from a product’s announcement to it being implemented in most installations. I really don’t think anything much has changed. So you wouldn’t write code that depended on a feature your customers (or users) don’t have yet. Well actually you would: You’d just expect it to take a while for them to catch up. And you certainly wouldn’t make it immediately mandatory.
And so it is with HTML5. Mark helps out considerably with the “support of unsupportive browsers” issue by recommending the Modernizr HTML and CSS Feature Detection package. (You can follow them on Twitter: here) I’m sure there are other techniques for handling this but Mark’s right in pointing out this one hunts for capability rather than a named browser. Given some of the features of HTML5 are awfully similar to those provided by javascript frameworks such as Dojo, I’d not be surprised if these frameworks could be relied on in the future to do feature detection (simulating it if not present in the browser). Good examples of this are input elements in forms, much enhanced in HTML5.
At this point I’m reminded I haven’t outlined what’s in HTML5. So here’s a high-level list:
The Canvas drawing surface (which I have a “Production” application built around).
Offline applications (which I’ve experimented with).
Video (which looks a mess and set to remain one).
Geolocation (which I’ve not used in the HTML5 context but have, of course, in Social Networking and other applications).
Local Storage (a better replacement for cookies).
Forms enhancements (which look really nice). Rather than my attempting to create graphics of them see here for some input type examples.
Microdata (a replacement for the non-standard Microformats and the highly-incomprehensible RDFa – as a way of annotating parts of web pages with structured data).
So lots of really valuable things. But how does the book do?
Given the earliness of its publication I think it does very well. From the above I think you can see it pragmatically handles the issue of support – which is going to be key. It also describes each feature very well, with good clear examples. It also adds a historical backdrop – particularly when talking about how unknown elements are handled – so it gives you a good idea how we got here.
So, I think HTML5 is more than ready to be played with and this book is a very good one to get you started. (I’m assuming you’re not starting from a “zero knowledge of HTML” position.) It doesn’t tackle CSS3 and I’ve yet to find anything that does. When I find such a book I’ll probably buy it and review it here.
Mainframe, Performance, Topics 