by George Scholassnagle
(c) Copyright 2004
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There is little that is cutting-edge in this book. It covers technology that still is useful but has been out for a while (hence the 2004 copyright). It falls short of being a classic. Nonetheless, the skills contained in this book are still useful to contemporary PHP development that continues to this day.
In particular, I found the benchmarking section helpful to my own PHP development. Schlossnagle taught me how I can track how much CPU time particular pages are using in my applications. This may not be useful for low-level websites, but it is helpful for larger applications that do some computation or database calls as a part of their feature set.
This book also has helpful texts suggested for further reading. Mainly books, not papers, are cited in these references. As a compulsive bibliophile, I like picking up on references to read further down the road.