This book has proven quite handy of late. I flip through it's pages at least once a day, and quite often more than that as I'm building my personal site as well as a couple of sites for clients. I have a pretty solid foundation in programming concepts from Perl and JavaScript as well as PHP, so I am using the book as a reference manual as opposed to a linear text-book. There are some concepts which I've had to look up on the Web as they were considered basic knowledge.I recommend the book for those who are comfortable with some programming, but not those new to the language.