Learn Interfaces — a key concept for LLD interviews.
Interactive — Try it yourself!
How to use
1Click animals to see polymorphism in action
2Notice: each animal "implements" the makeSound() interface differently
3The caller doesn't know the concrete type — just calls the interface method
4This is programming to an interface, not an implementation
In a nutshell
An interface defines a contract — "any class that implements me MUST have these methods". It doesn't say HOW to implement them. This lets you swap implementations without changing the calling code.