What kind of data or information would I want to store in the User Info panel for an Entity?

The Xcode Data开发者_StackOverflow中文版 Modeler has this user info panel at the top right, second tab from left. It asks for key and value. What would I store in there? What is this useful for?

From Core Data User's Guide:

Many of the elements in a managed object model—entities, attributes, and relationships—have an associated user info dictionary. You can put whatever information you want into a user info dictionary, as key-value pairs. Common information to put into the user info dictionary includes version details for an entity, and values used by the predicate for a fetched property.

It's really just a free form dictionary in which you can park any info you think you might need to have about an entity in the future. Most often this info is used in versioning.