What are Good Things to Know in a C# Interview?

Question

What are Good Things to Know in a C# Interview?

Off the top of my head, I have come up with this list:

•      SOLID mythodology.
•      Dependency Injection
•      Levels of Try, Catch, throw, and finally statements and how they work
•      The tenants of Object Oriented Programming such as polymorphism, enacpsulation, etc.
•      Unit Testing (are interfaces used somehow)
•      The difference between an abstract class and interface
•      garbage collection and when to override or overload it
•      difference between override or overload
•      Is there inheritance in C# ?
•      What is an interface used for?

I am posting this here to see of anyone can add to this list.  I am asking about general topics, not specific interview questions.