Usable indoors and out, a quadcopter is great for any hobbyist. These miniature remote-control helicopters can provide hours of entertainment and serve an important role in many fields of research. As the name suggests, each quadcopter has four rotors, deployed in two counter-rotating pairs. Each rotor has its own electric motor, which simplifies the controls, as the quadcopter is able to use fixed pitch rotors for attitude controls. You can buy quadcopters fully assembled, or as kits; you can even buy the components separately on eBay and build a quadcopter of your own design. Available parts include everything from motors and rotors, to frames and controllers. There are options for people who just want to fly a quadcopter and other choices for people who want to build their own and see just what they can do. Every quadcopter has four motors and a remote control, but beyond that, the sky is the limit. Pick up your own quadcopter and let your imagination fly.