A rhetorical question is a figure of speech in the form of a question that is asked in order to make a point and without the expectation of a reply. The question is used as a rhetorical device, posed for the sake of encouraging its listener to consider a message or viewpoint. Though these are technically questions, they do not always require a question mark.
For example, the question "Can't you do anything right?" is asked not to gain information about the ability of the person being spoken to, but rather to insinuate that the person always fails.
While sometimes amusing and even humorous, rhetorical questions are rarely meant for pure, comedic effect. A carefully crafted question can, if delivered well, persuade an audience to believe in the position(s) of the speaker.
In simple terms, a question asked more to produce an effect than to summon an answer.
Famous quotes related to rhetorical question:
“Art has always been this—pure interrogation, rhetorical question less the rhetoric—whatever else it may have been obliged by social reality to appear.”
—Samuel Beckett (1906–1989)