This is the starting point for developing a model of entities with which a registry needs to engage. To start with, we'll simply create a list of 'things' and add definitions to them:

• data centre (or center)
  • definitions here
• service
• interface
• data collection
• dataset (which I think is just my term for data collection)
• database
• table
• mirror
• copy
• application
• function (as in what an app does)