Explain the difference between Factory Method and Abstract Factory patterns.

Short answer: Factory Method: Defines an interface for creating an object but lets subclasses decide which class to instantiate. It uses inheritance and relies on subclass overriding. Abstract Factory: Provides an interface to create families of related or dependent objects without specifying their concrete classes. It uses composition and is useful when you need to create multiple related objects together.

Real-world example (ShopNest)

ShopNest payment fees use Strategy: IFeeCalculator with UPI/Card implementations chosen at runtime.

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.