I know that an identity is the subset of profile data that uniquely represents a person in one or more repositories, and additional information related to the person.
For example, an identity might be represented by unique combination of the first, last, full name, and employee number of a person. The data might also contain additional information such as phone numbers, manager, and email address. A data source can be a customer's user repository or a file, a directory, or a custom source.
I'm always find examples on how to create identity feeds but not an use case (an example maybe of a file.feed or file.zip content)