Deloitte Developer interview questions

What is .NET, and how does it work? Explain the difference between .NET Framework, .NET Core, and .NET 5/6/7. What is the Common Language Runtime (CLR)? What is the role of the .NET Garbage Collector (GC)? OOP & C# Concepts: Explain the difference between an abstract class and an interface. What are delegates and events in C#? What is the difference between ref and out parameters in C#? What is the difference between String and StringBuilder?