Archiving with XML Property Lists

Mac OS X applications use XML propertylists (or plists) for storing things such as your default preferences, application settings, and configuration information, so it’s useful to know how to create them and read them back in. Their use for archiving purposes, however, is limited because when creating a property list for a data structure, specific object classes are not retained, multiple references to the same object are not stored, and the mutability of an object is not preserved.