The book you're holding in your hand (or reading on the screen) owes its genesis to a tongue-in-cheek exchange with Steve Fleischer of Flying Tiger Web Design (www.flyingtigerwebdesign.com), who suggested I should write Powers Object-Oriented PHP. Actually, he phrased it rather differently. If you take the initial letters of the suggested title, you'll get the drift . . . But Steve had an important point: he felt that books on object-oriented programming (OOP) frequently assumed too much prior knowledge or weren't easily adaptable to PHP in a practical way. If you like what you find in this book, thank Steve for planting the idea in my brain. If you don't like it, blame me, because I'm the one responsible for writing it the way it is.

Thanks must also go to everyone at Apress/friends of ED for helping bring "my baby" into the world. Books are uncannily like real babies. This one took exactly nine months from conception to birth with the expert help of editor Ben Renow-Clarke, project manager Beth Christmas, and many other "midwives." I owe a particular debt of gratitude to Seungyeob Choi for his perceptive technical review. Seungyeob's eagle eye and deep knowledge of PHP and OOP saved me from several embarrassing mistakes. Any remaining errors are my responsibility alone.

I would also like to thank everyone who has supported me by buying this or any of my previous books. I realize not everyone can afford to buy books, but the royalties from new—not second-hand—books ensure that authors get some reward for all the hard effort that goes into writing. Even the most successful computer books can never aspire to the stratospheric heights of Harry Potter, so every little bit helps—and is much appreciated.

The biggest thanks of all must undoubtedly go to the developers of PHP, who have given the rest of the world a superb programming language that continues to go from strength to strength.