A chimney above the Sistine Chapel in the Vatican will signal the election of a new pope and leader of the Catholic Church.

Add Yahoo as a preferred source to see more of our stories on Google. A movie’s premiere is something of a “known known” that can be choreographed months in advance to maximize its odds of success.

Donald Rumsfeld popularized the concept of known knowns, known unknowns, and unknown unknowns (though 'popularized' might be the wrong term for a convoluted quote from a Secretary of Defense about the ...