Whats newtons and laws of motion.

Newton's first law states that every object will remain at rest or in uniform motion in a straight line unless compelled to change its state by the action of an external force. This is normally taken as the definition of inertia ... For an external applied force, the change in velocity depends on the mass of the object.-google

my own words-it is mostly just saying that if a rock or ball is in one place then it will have to be moved by force and that will cause motion the external force or something other then the rock or ball being you and the velocity depends on how hard you push or move the object