A data schema is a description of a set of data. P3P includes a way to describe data schemas so that services can communicate to user agents about the data they collect. A data schema is built from a number of data elements, which are specific items of data a service might collect.
Data elements in a data schema can have the following properties:
Data element name. The name of the data element is used when a P3P policy includes this data element in a <DATA> element. This is required on all data elements.
Descriptive name or short name. A data element's short name provides a short, human-understandable name for the data element. The short name is not required, but it is strongly recommended.
Long description. The long description ...