firephp is a plugin for firebug, the web development plugin for firefox, that allows php scripts to talk to a firebug panel.
firephp installs alongside firebug and provides a simple php library to bridge the two. firephp provides a window of insight into your php applications, with a simple debugging interface that won’t interfere with your page content. if you already use firebug on php-powered applications, firephp is definitely worth a look. here’s a quick guide to getting started.