What is the diffrence between an Abstract class and Interface?

• Abstract classes may have some executable methods and methods left unimplemented. Interfaces contain no implementation code.
• A class can implement any number of interfaces, but subclass at most one abstract class.
• An abstract class can have nonabstract methods. All methods of an interface are abstract.
• An abstract class can have instance variables. An interface cannot.
• An abstract class can define constructor. An interface cannot.
• An abstract class can have any visibility: public, protected, private or none (package). An interface's visibility must be public or none (package).
• An abstract class inherits from Object and includes methods such as clone() and equals().