National Geographic answers all the questions about technology, biology, chemistry, physics, math, engineering, computers, and mechanics—in an indispensable book that reveals the science behind virtually everything. How does the voice of a distant radio announcer make it through your alarm clock in the morning? How does your gas stove work? How does the remote control open your garage door? What happens when you turn the key in the ignition? What do antibiotics really do? Divided into four big realms—Mechanics, Natural Forces, Materials & Chemistry, Biology & Medicine— takes readers on a fascinating tour, using plain talk, colorful photography, instructive diagrams, and everyday examples to explain the science behind all the things we take for granted in our modern world.