(idiomatic) Used to indicate agreement, as if one would have wanted to say what a previous speaker has said, without change or qualification

What are you thinking about?

(UK, Ireland, colloquial, US, obsolete) Expressing mock despair at somebody's outrageous behaviour.

(rhetorical question) A rhetorical request for some real news, on hearing a report that was not news because it represents a continuing predictable and unsatisfactory situation.

What is the date? (used to request the current date)

A person's personality is more important than their physical looks.

(colloquial, humorous) What's up?

(idiomatic) Used to express disappointment about someone's uncharacteristic or abnormal past actions.

(dated) Synonym of know what is what

(idiomatic, US) As an interrogatory, indicative of a nonchalant attitude towards potential criticism, not caring about what other people think, confident and self-possessed.