This book covers two totally separate topics and so doesn't really cover either of them in great depth.
HTML 5 is the proposed new version of HTML and XHTML to replace HTML 4.01 and HTML 1.0. The proposed new standard includes both tags and attributes that should be extremely useful as well as some that are completely unnecessary. This book distinguishes between the two concentrating on demonstrating how to use the useful ones and how you can also make many of them backwards compatible to earlier browsers.
CSS 3 is the new CSS standard that is broken up into a number of modules - some of which have already been finialised while others are not much further along in their development than HTML 5 is. Here the book doesn't distinguish so welll between the different options and covers some of those parts of CSS that may undergo great change prior to their being finished. As the book doesn't really distinguish between the different levels of CSS 3 support, you may end up with pages that need more work in the future to change them to support the changes as they occur (while this is also true of the HTML, with those it is probably more a matter of which will be retained in the new standard rather than what they mean and the book concentrates on the ones that are most useful and therefore most likely to be retained).
The book does choose an interesting example web page to demonstrate most of the techniques that it covers. The page is of a sort that at least some sites might like to use and is one where the code being demonstrated is really required in order to produce the flexibility that you would want in such a page. In this sense the demonstrated code really is for the real world as the title suggests.
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This article written by Stephen Chapman, Felgall Pty Ltd.