Programming PHP
I'm planning to "kick it up a notch" with learning PHP in the coming months. Just
ordered this book (Programming PHP 2nd edition) should be getting it in the next few days. Also since it is
just above $25 you get free shipping (in the US and UK, in Canada you will have
to purchase an additional item, hey...). Assuming all else is equal (reputation and topics), I usually pick books based on 3
criterias:
- Popularity
- Reviews
- Published date
Following these 3 parameters "Programming PHP" is the best.
Programming PHP
by Kevin Tatroe, Rasmus Lerdorf, Peter MacIntyreBook description from Amazon:
Programming PHP, Second Edition is the authoritative guide to PHP
5 and is filled with the unique knowledge of the creator of PHP (Rasmus
Lerdorf) and other PHP experts. When it comes to creating websites, the PHP
scripting language is truly a red-hot property. In fact, PHP is currently used
on more than 19 million websites, surpassing Microsoft's ASP .NET technology in
popularity. Programmers love its flexibility and speed; designers love its
accessibility and convenience.
As the industry standard book on PHP, all of the essentials are covered in a clear and concise manner. Language syntax and programming techniques are coupled with numerous examples that illustrate both correct usage and common idioms. With style tips and practical programming advice, this book will help you become not just a PHP programmer, but a good PHP programmer. Programming PHP, Second Edition covers everything you need to know to create effective web applications with PHP.
More information on Programming PHP 2nd edition:

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Programming PHP
Forgot to follow up on this.
I purchased this book months ago now. It's a good PHP book. It's not the book of the century but a good, decent book on PHP. I personally wished it offered more advanced tips on performance and the likes but a single book can't have it all. This book helped me learn PHP so if you want to learn PHP this is a good book. If you already know PHP this is probably not the book for you.
I still have this book next to me and use it once in a while. I also use the online site php.net a lot for reference to functions, it's nearly faster then opening the book.
I will probably take another look at this book next time I'm on vacation to see if I can extract more knowledge from it...