Actually is Burmese or Myanmar people the right term to address people there? I'm sorry if calling people there Burmese offensive. ^^;

I would like to ask:

1. Is calling a friend 'thoun-thaw' or 'ah-thaw' rude? If yes, why?

2. What is the difference between 'thoun-thaw' and 'ah-thaw'?

3. How do you write these two words in Burmese/ Myanmar language?

4. How do you actually pronounce it?

That's all. Thanks guys! ^^