Interfaces are wonderful for creating reusable code, as well as enabling us to reuse or make better use of the functionality SFDC already provides us.
The Apex Developer's Guide tells us how to create our own interfaces, but the Table of Contents only gives one native interface under "Interfaces" (that being Iterators).
However, I know SFDC gives us at least a few more (Batchable, Schedulable, Queueable, Iterable).
What other interfaces are available to us? What are their intended use cases?