27 Most Important .NET Fundamentals Interview Questions and Answers (2026)

.NET fundamentals are the bedrock beneath every C# line you write from the Common Language Runtime’s JIT magic to the type system, garbage collector, and base class libraries that tie it all together.

Grasping how these pieces interact not only sharpens your day-to-day coding instincts; it also gives you the interview edge, letting you explain why your code behaves, scales, and performs the way it does when everyone else is stuck at “it just works.”