1) a question when one is curious about what is going on around him.
2)A popular greeting greating used instead of "hello".
3) A state of confusion when used in a situation where both definitions intertwine.
eg. when you have just met someone whom you know and who may be curious about a situation or the goings on around you.
A phrase that can be used universally in most situations.
It is generally said when greeting another person, however it is also quite acceptable to out of excitement as a way of expressing joy.