The example you XML you included is from a property list [0]. While there is more than one implementation, there is essentially a defacto implementation. XML is

The example you XML you included is from a property list [0]. While there is more than one implementation, there is essentially a defacto implementation. XML is only one format, and data is relatively strongly typed. All of the types provide documentation regarding exactly how they are serialized, deserialized. In this case, the string value in the dictionary is specific to OmniGraffle. It's format is proprietary, but the only producer is also the consumer. Omni may or may not have a formal spec indicating the format of this value. You'd have to work there to find out. [0] http://en.wikipedia.org/wiki/Property_list http://en.wikipedia.org/wiki/Property_list