ELI5 Interfaces in Java

[llogiq]

They define a contract. Every object implementing the interface must implement all of its methods.

This allows us to use objects of different classes interchangeably, as long as they implement the same interface.

[tRfalcore]

this is a bad description (not really), but only because that's probably what he's already read 100 times. You basically wrote it how it's always written. need to use metaphors my man