questions: possible ways of asking what something does

Question

1. What does your program?
2. What does your program do?
3. What your program does?
4. What is it that your program does?
5. Your program does what?

Can anyone help me understand how these questions differ in meaning and whether they're correct, less/ more informal, and when they can be used? Am I missing another way of asking what something does? Thank you in advance.

Answer 1

1. Grammatically incorrect / Incomplete question (needs a verb)
2. Grammatically correct and is the most formal way in the list
3. to 5. are less formal but asking the same thing.