If your just beginning to learn about HTML, XHTML & CSS then this book is a must as this book will teach you how to build basic websites and learn what each tag does and how and where to use it.  When you finish this book you will have saved yourself a whole bunch of time trying to learn from tutorials and other websites as you will be able to build a fully functional website in no time.  Also what is best with this book as it comes with a companion website in which you can download all the mini tutorials that this book as to offer so you can see what their examples look like and learn from how the coding is set up as well.  With CSS they list ever current tag that CSS uses to help design great websites without the need to hand code each individual page as CSS is used to help globally design your website and save you many hours of work as well.  This book also discusses some html editors that person can use, both commercially or free.