*Could* make a pretty handy dictionary, *if* you can ignore the irritating, inaccurate, and uneducated claims and editorials (mostly found in the introduction/tutorial) all based on the premise that HTML is a programming language.
page xxiii: "What in HTML is called a 'tag' is called a 'structure' or 'function' in other languages."--WRONG. HTML tags are simply *tokens* which the browser *parses* to determine the output.
page xxvii: "No other computer programming language comes close to HTML's forgiveness. Try submitting [a text document containing only the string] 'A Simple Page' to Basic, Pascal, C, or any other language. None of them will simply display the words. All of them will choke and throw out an error message."--WRONG!! First, there's no such thing as submitting anything to a language. You *can* 'submit' input to a *program* written in a programming language- such as an internet browser- and if that program is *designed* to handle that input, it *will* simply display the words. Otherwise, if the program is *not designed* to handle the input, it *will* choke and spit out an error message.
It is irritating to have spent money on a developer's reference, written by someone who clearly does not have a grasp of programming *basics*.