Java interface as reference type?
855
What does it mean to "program to an interface"?
75499
Determine if a Class implements a interface in Java
150870
Java - Method name collision in interface implementation
114816
Is null reference possible?
94336
How are references implemented internally?
5245
When should I use an interface in java?
91796
How do I implement interfaces in python?
66575
Why use an interface in Apex?
10143
Why does (does it really?) List implement all these interfaces, not just IList?
12387
What is "Best Practice" For Comparing Two Instances of a Reference Type?
94251
Is it possible to assign a base class object to a derived class reference with an explicit typecast?
100925
Does an interface by default extend Object?
80633
Java - declaring from Interface type instead of Class
139818
Why implement interface explicitly?
33115
Interface naming in Java
31730
Why do we use Interface? Is it only for Standardization?
6853
Interface vs Abstract Class (general OO)