Quadrotor

A quadcopter, also called a quadrotor helicopter, quadrocopter, quadrotor, is a multicopter that is lifted and propelled by four rotors. Quadcopters are classified as rotorcraft, as opposed to fixed-wing aircraft, because their lift is generated by a set of revolving narrow-chord airfoils. Unlike most helicopters, quadcopters generally use symmetrically pitched blades; these can be adjusted as a group, a property known as 'collective', but not individually based upon the blade's position in the rotor disc, which is called 'cyclic' (see helicopter). Control of vehicle motion is achieved by altering the pitch and/or rotation rate of one or more rotor discs, thereby changing its torque load and thrust/lift characteristics.

Quadrotor is helicopter that has four rotors for stability.

Looking at making one using:
11.1v Brushless 13000-RPM motor for each rotor
11.1V 2200mAh Lithium Polymer Rechargeable Battery to power it
digital 1.7V to 2.75V 3-AXIS ACCELEROMETER
digital 2.4V to 3.6V 3-AXIS GYROSCOPE
5v RaspberryPi to calculate everything.

Looking at [1] for how to use the gyro and accelerometer together well.
Found out that the two opposite motors need to be going in one directions and the others in the opposite direction.
good link for info about quad rotors and making one: [2]