Handshaking is about as prevalent in the business world as pencil skirts, suits, and coffee. But why the heck do we do it? Shaking hands has a long and storied history, and there may be a peculiar reason we greet people this way. A recent study suggests we outstretch our hands and shake other people’s hands to check out how they smell; researchers believe handshaking offers a socially acceptable way for humans to communicate by way of smell. Whether we’re consciously aware of this or not, handshaking is universal—and there is such thing as a good shake and a bad one. Check out the infographic below to learn how to hone your hand-shaking skills.