Whenever people ask me to recommend a good learning book about general WordPress stuff, they pretty much always get the same answer. Well, they always got the same answer. Because as of today Professional WordPress has a second edition. Not familiar yet with Professional WordPress? This is what Brad Williams, one of the authors, has to say about it on his blog:
Professional WordPress is a book written by programmers for programmers. We take a more in-depth look at WordPress to help explain how WP works from the inside out. The book offers an overview of the WordPress loading process and steps through exactly what happens when a WordPress-generated web page is displayed. The book also covers extending WordPress functionality through custom plugins and creating website designs with custom themes and child themes.
Have you picked up or ordered your copy yet?