Being right-handed is the form of handedness characterized by greater coordination in the right hand and arm, and strong preference, in one-handed tasks, for using the right rather than left limb.
A variety of studies suggest that 70% to 90%[1][2] of the world population are right-handed, as opposed to left-handed or having other handedness traits.
There is no prevailing theory that explains why right-handedness is so much more common than left-handedness.[2] Neurologically, the motor skills of the right side of the body are controlled by the left hemisphere of the brain, so researchers believe the explanation may ultimately be found in the differences between the two halves of the brain. For example, a recent study found that right-handers use the right side of the brain to focus on an entire image, but the left side of the brain to focus on details within an image.[3] This observed difference, like many others, shows the effects of right-handedness but does not clearly indicate its cause.
http://en.wikipedia.org/wiki/Right-handedness
