Centripetal force means "center seeking" force (centrum "center" and petere "to seek"). The Centripetal Force is the force directed towards the center of an object's circular path. Any motion in a curved path represents accelerated motion, and requires a force directed toward the center of curvature of the path. Sir Isaac Newton stated: "A centripetal force is that by which bodies are drawn or impelled, or in any way tend, towards a point as to a center."
The direction of the centripetal force, which makes the body follow a curved path, is always orthogonal to the velocity of the body, directed along the radius towards the center. Centripetal force is generally the cause of circular motion.
Centripetal force = mass x velocity2 / radius
The centripetal force is proportional to the square of the velocity, meaning that doubling the speed will require four times the centripetal force to keep the motion in a circle.