1. static keyword
2. const vs readonly
3. internal keyword
4. sealed keyword
5. override vs overload
6. interface vs abstract class
7. value type vs reference type
8. stringbuilder vs string
9. explicit vs implicit
10. params keyword
11. class vs structure
12. lock keyword
13. typeof keyword
14. ref vs out
15. virtual vs abstract
16. event vs delegate
17. what’s generic
18. box vs unbox
19. what’s reflection
20. appdomain vs thread vs process
21. what’s indexer
22. new keyword
23. using keyword
24. what’s exception
25. extern keyword
