Subject Interface (IImage):?

Short answer: This is the common interface that both the real object (RealImage) and the proxy object (ProxyImage) implement. It defines the method Display() that both concrete classes must implement. public interface IImage

Example code

{ void Display(); }

Real-world example (ShopNest)

Use a GoF pattern in ShopNest only when it removes duplication or makes a change safer—explain the problem it solves in the interview.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.