1. A method to model the structure of an item with meta-annotations, comprising: defining the structure of an item with a meta-model employing meta-data annotations, the meta-model at least including one meta-relationship and at least one meta-class, the at least one meta-relationship describing one or more relationships between meta-classes, the at least one meta-class being a class encapsulating data employed to represent another class, and the at least one meta-class is identified via a globally unique identifier; and reading the meta-data annotations from computer readable media to determine the structure of an item.