Covers licensing issues for developers distributing applications in PHP. Includes links to annotated version of the relevant licenses and other related resources.

This is a soap integration for PHP (pear package).

Volunteer coders dedicated to providing coders with quality assurance.

Server-side HTML embedded scripting language. It provides web developers with a full suite of tools for building dynamic websites: native APIs to Apache and other web servers; easy access to MySQL, Sybase, Oracle, and other databases; IMAP; LDAP; HTTP...

Adds security hardening features to the language. Include news, libraries, Hardening patch, services advisories, a forum and a system for advanced protection of installations.

A full-featured profiler/debugger that is loaded as a zend_extension. It aims to be an analog of C's gprof or Perl's Devel::DProf. Offered from PHP.net [Open source, GPL]

Provides a framework to benchmark PHP scripts and function calls. The PEAR site also contains hundreds of other pre-built packages. [Open source, GPL]

Quick reference that lists all PHP functions.

Complete and hyperlinked manual documents and explains all elements of PHP. Includes FAQ section and user comments.

A list of Frequently Asked Questions about PHP and their answers.