When switching to an Eclipse-based IDE like Zend Studio, some developers become annoyed by the help they are provided in the code editors. Auto closing of braces, parentheses, tags and the like is helpful for beginners and advanced developers who got used to this feature. But for those migrating from tools where they used to have the full control in the editor, this is nothing but a hurdle.
Fortunately, you can switch this off. As you may guess it is hidden in the ocean of preferences. The easiest way to find it is to enter "typing" in the filter field of the Preferences dialog.