Can you instantiate an abstract class?

Short answer: No, abstract classes cannot be instantiated directly. Must be inherited by a derived class which implements abstract methods. abstract class Shape { public abstract void Draw(); } // Shape s = new Shape(); // Not allowed

Example code

class Circle : Shape { public override void Draw() => Console.WriteLine("Circle"); }

Real-world example (ShopNest)

Checkout calls IPaymentGateway.Charge(). Razorpay and Stripe adapters implement the same interface, so ShopNest can switch gateways without rewriting the order service.

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.