How do you categorize or group tests in MSTest?

Short answer: Use the [TestCategory("CategoryName")] attribute to group tests for filtering. [TestMethod] [TestCategory("Integration")] public void IntegrationTest() { }

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.