These joys of technology are available cheaply due to the mass production of the parts (Gyros, Accelerometers, Pressure sensors, GPS receivers, Electronic Compasses etc.) for use in Smart Phones, I-Devices, Android devices and Wii controller devices. Thanks to some dedicated Techno-wizards that see the world in code (off the wall reference to "The Matrix) these devices all come together in a single almost magical, electromechanical implementation that uses complex control algorithms to sense motion in six axis's using Gyro's and Accelerometers (and sometimes many other sensors as in the case of ArduPilot) to determine relative location, level and direction of travel so that the correct signals will get to the correct motor at the correct instant in time to produced the desired movement commanded by the "Pilot/Operator". This is about as close to the Jetson's and Star Trek that it gets for the common man today.
KK2 is easy to use and VERY good at allowing precise control over the craft it is installed on while allowing the more technically inclined to alter settings to precisely match the flight characteristics of the frame and motor / esc combination and even hack the code to improve it.
Let me sum it up: Multirotors are the Di-lithium Crystals where Science and Science Fiction meet and mix thoroughly transmuting the dreams of a new generation of amateur scientist into a powerful reality.
Thurmond