For those who do not like formulas in the special of relativity, as a close illustrative example, let us cite a airplane flying high in the sky. Its dimensions are reduced, and the speed of movement (time process) is slowed down. For passengers of an aircraft, the same phenomena on the earth's surface (for example, moving cars) also look like this. Who flew on an airplane, probably remembers that feeling of unreality when viewed from a high altitude on the tape of an automobile road, where cars moving at high speed seem almost frozen in one place. Time for them seemed to stop. There is an equality between the observer on the earth's surface and the observer in the airplane (mutual "contraction" of lengths and mutual "slowing down" of temporal processes - velocities of motion), similar to how it occurs in the special of relativity. The only difference is that in our example the variable is the relative distance between two observers (geometric relativity), whereas in the special of relativity the variable is the relative speed between the two reference frames (kinematic relativity).