I've had several editions of this book and they're the best of the best. In fact, it's how I started out after I'd read all the other confusing books out there and I still use it because virtually EVERYTHING is covered including kerning, word-spacing and other odds and ends that you normally don't come across.
What's so great about this book?? Clarity and simplicity. She explains everything in detail and you can pick out what you want, when you want. No need to start from the beginning and work your way through - just find the section you need and get started.
This book is in colour, too. Every example has a detailed, friendly picture of a page that she (presumably) made herself and next to it will be the appropriate HTML. Every example also has real life tips, for example on the difference between the browsers (particularly bad old non-compliant IE).
A list of the chapters:
Intro (CSS and browser support, XHTML vs HTML)
1 - Web page building blocks (URLS, Doctypes)
2 - Working with Web Page Files
3 - Basic (X) HTML structure
4 - Basic (X) HTML formatting
5 - Images
6 - Links
7 - Style sheet building blocks
8 - Working with style sheet files
9 - Defining selectors
10 - formatting with styles
11 - Layout with styles
12 - dynamic effects with styles
13 - style sheets for handhelds
14 - style sheets for printing
15 - Lists
16 - Tables
17 - forms
18 - Video, auio and other multimedia
19 - scripts
20 - a taste of javascript
21 - symbols and non english characters
22 - testing and debugging webpages
23 - publishing your pages on the web
24 - getting people to visit
25 - syndication and podcasting
There are some very useful reference apendices at the end, and a colour chart.
My only gripe is that I couldn't find anything about iframes, but I have an old copy of her book and that's in there.
As far as I'm concerned this is the only book on HTML / XHTML and every time she brings out a new version I buy it, as it's always up to date.
Brilliant!