Formal: คุณชื่ออะไรคะ/ครับ? (khun cheu a-rai ka/khrap?)
* This is the most polite and respectful way to ask.
* "khun" means "you" (formal)
* "cheu" means "name"
* "a-rai" means "what"
* "ka" is used by women, and "khrap" is used by men
Informal: ชื่ออะไร? (cheu a-rai?)
* This is a more casual way to ask, and is appropriate when speaking to friends or people you know well.
Note:
* When speaking to a stranger or someone older than you, it's always best to use the formal form.
* You can also add "khrap" or "ka" at the end of any sentence to make it more polite.