How much do you know about . . . Obesity Sleep Meteors Aliens Bees Sperm banks Sex in space Duct tape Germs Airport security Death Ancient weapons Rats The Internet Birth Weather Milk Mosquitoes Your body Space disasters DISCOVER'S 20 Things You Didn't Know About Everything is the first book written by the editors of the award-winning DISCOVER magazine. Based on DISCOVER'S most eagerly awaited monthly column, "20 Things You Didn't Know About," this original book looks at many popular—and sometimes unexpected—topics in science and technology, and reveals quirky, intriguing, and little-known facts. Whether you're just curious or think you already know everything, this book is guaranteed to expand your mind.