What is the Moq framework and how is it used in .NET?

Short answer: Moq is a popular, open-source mocking library for .NET that enables developers to create mock objects, set expectations, and verify interactions in unit tests, helping isolate dependencies easily.

Real-world example (ShopNest)

ShopNest unit tests cover pricing and discount rules so a bad coupon change fails in CI before customers see it.

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.