People generally feel pretty good when they laugh, and we expect people are happy when they hear it. Even when you laugh as a distraction, or in reaction to something unpleasant, it helps put you in better spirits. Why is that?
It turns out it’s not just a human thing. Laughter is observed in many mammals, of all ages. It can be observed during play, tickling, and often around friends. Laughter is also a social thing. We are thirty times more likely to laugh when we’re with other people than when we are alone.