an abstracted class is a class that you can implement some method and make other abstracted without implementation and contains fields and you can create a reference from a abstracted class but you cant create an object a concrete class is a normal class you can create reference and object from it and you must implement all methods and you can have fields an interface is something to class it is created for inheritance purposes you can only create an abstracted method inside it without implementation no fields or normal method are allowed another difference that you can inherit multiple interfaces but only one class