We've all heard the phrase "Laughter is the best medicine." But why do we laugh in the first place? It seems that laughing might be a little more hard-wired into us than you might think. Infants laugh very early in life, usually learning how to laugh before they can speak. Not only that, but people that are born blind and deaf can still exhibit laughter. One study found that the laughter produced from deaf participants was fundamentally similar to that produced by normally hearing individuals, backing up the idea that laughter is grounded in human biology. It's also been theorized that laughter predates human speech by potentially millions of years, being a simpler form of communication. Laughter is thought to have likely helped earlier people negotiate group dynamics and establish hierarchy. I can't even imagine trying to explain that I'm a little goofball using only laughter! So if laughter actually is instinctually part of humans, then why do people laugh? It seems like laughter is more of a way for people to better handle stress and make situations feel less threatening than laughter only being about things that we find to be funny. In practice, with a study of 1,200 people that laughed spontaneously in their natural environments, only about 10-20 percent of the laughing episodes followed anything the researchers found to be joke-like. Finding something funny still seems to play a part in why we laugh some of the time, but laughing to make yourself feel better about your next difficult exam might be just as probable as cracking up over that joke you just heard.