Formal:
* Jak się pan/pani ma? (How are you, sir/madam?) - Used for someone older, in a position of authority, or someone you don't know well.
Informal:
* Jak się masz? (How are you?) - Used for friends, family, and people you know well.
* Co u Ciebie? (What's up?) - A more casual way to ask.
Other variations:
* Jak leci? (How's it going?) - Very informal, used with close friends.
* Jak tam? (How's it going?) - Another casual way to ask.
For example:
* If you're speaking to your teacher, you would use Jak się pan/pani ma?
* If you're speaking to your friend, you could use Jak się masz? or Co u Ciebie?
* If you're speaking to a younger sibling, you might use Jak tam? or Jak leci?
It's always best to err on the side of formality, especially if you are unsure about the appropriate level of informality.