Humor, like pornography, is famously difficult to define. We know it when we see it, but is there any way to figure out what we really find funny? In this fascinating investigation into the science of humor and laughter, neuroscientist Scott Weems uncovers what’s happening in our heads when we giggle, guffaw, or double over with laughter. Beginning with the premise that humor arises from inner conflict in the brain, Weems explores such issues as why surprise is so important for humor, why computers are terrible at recognizing what’s funny, and why cringe-worthy stereotypes make us laugh the hardest. From the role of insult jokes to the benefit of laughing for our immune system responses, Ha! reveals why humor is so idiosyncratic, and why how-to books alone will never help us become funnier people. Packed with the latest research, amusing anecdotes (and even a few jokes), Ha! is a delightful tour of why humor is so important to our daily lives.