Error levels and their values in php

Value Constant Description
2 E_WARNING Non-fatal run-time errors. Execution of the script is not
halted
8 E_NOTICE Run-time notices. The script found something that might be
an error, but could also happen when running a script normally
256 E_USER_ERROR Fatal user-generated error. This is like an E_ERROR set by
the programmer using the PHP function trigger_error()
512 E_USER_WARNING Non-fatal user-generated warning. This is like an E_WARNING
set by the programmer using the PHP function trigger_error()
1024 E_USER_NOTICE User-generated notice. This is like an E_NOTICE set by the
programmer using the PHP function trigger_error()
4096 E_RECOVERABLE_ERROR Catchable fatal error. This is like an E_ERROR but can be
caught by a user defined handle (see also set_error_handler())
8191 E_ALL All errors and warnings, except level E_STRICT (E_STRICT
will be part of E_ALL as of PHP 6.0)