A personal data service (PDS) gives the user a central point of control for their personal information (e.g. interests, contact information, affiliations, preferences, friends). The user's data attributes being managed by the service may be stored in a co-located repository, or they may be stored in multiple external distributed repositories, or a combination of both. Attributes from a PDS may be accessed via an API. Users of the same PDS instance may be allowed to selectively share sets of attributes with other users. A data ecosystem is developing where such sharing among projects or "operators" may become practicable. [1]
The concept of a PDS can be differentiated from another closely related term, personal data store. "A personal data store is a physical repository for data over which an individual exerts access control. Again, the term itself does not imply where such a store lives on the network (i.e., in the cloud, on a local device, in a smart card, on a SIM, etc.)". [2] The word "store" implies that a personal data store actually stores personal data, [3] whereas the emphasis of a PDS is on providing a single point of control. [4] In summary, a 'personal data store' always stores data whereas, whereas a personal data service may or may not.