Abstract class and Interface

• Abstract class cannot be instantiated but can be derived.An abstract class can contain abstract methods or non abstract methods. Abstract class cannot be sealed class
• Abstract method cannot be private and should be declared in abstract class.
• Abstract method is implicitly virtual
• Abstract member cannot be static
• All the members of an interface are implicitly abstract
• All the members of an interface should be overridded.
• A class can inherit only multiple interfaces but it can inherit one abstract class
• An interface is not a class and has no implementation