The Xdebug extension helps you debugging your script by providing a lot of valuable debug information. The debug information that Xdebug can provide includes the following:

* stack traces and function traces in error messages with: - full parameter display for user defined functions - function name, file name and line indications - support for member functions * memory allocation * protection for infinite recursions

Xdebug also provides:

* profiling information for PHP scripts * script execution analysis * capabilities to debug your scripts interactively with a debug client