Measurements with very accurate clocks show that there are three distinct dimensions to the flow of time as represented by three different motions of matter and photons. Metaphysical time is the continuos idea of time that is common to all dimensions of time. Clocks divide individual dimensions of metaphysical time into intervals of physical time. Photon time, Earth time, and Gravitational time are the three separate dimensions of time that are each measured with a different kind of clock mechanism. All clocks divide time into intervals to quantify one of these three dimensions of time and motion.