解释学说注释

Question

I'm using Doctrine with CodeIgniter since idk, 5-6 days. And I know how to use it but I don't know WHY it's working.

An example is better, this is an example of my code for an entity :

/** @Entity */
class User
{
    /**
     * Many Users have Many Groups.
     * @var Collection
     * @ManyToMany(targetEntity="Group")
     */
     private $groups;

     //
     //
}

I don't understand how the "process" , the "heart of Doctrine" can interpret the things in comments. Like the annotation @ManyToMany for example ? How it is possible for the PHP to understand and to execute that is present into /* */ ?

Thanks for help me to understand this thing.