This section lists standard predefined classes. Miscellaneous extensions
    define other classes which are described in their reference.
   
     These classes are defined in the standard set of functions included
     in the PHP build.
    
- Directory
 
        The class from which dir is instantiated.
       
- stdClass
 
       
- __PHP_Incomplete_Class
 
       
     These additional predefined classes were introduced in 
     PHP 5.0.0
    
- exception
 
       
- php_user_filter