One of the biggest unsolved problems in physics is explaining what time is. The paper explains what time is in kinematics theories. It has been proved that in the kinematics of Special Theory of Relativity (STR) and Special Theory of Ether (STE) time is measured by the light clock. Therefore, all properties of time in kinematics result from the properties of a signal clock. The paper explains the time dilation phenomenon on the basis of STE. The presented explanation is not only a classic description of time dilation, but is based on the construction of an innovative technical model of this phenomenon. Time dilation is due to the properties of the light clock. It is a natural property of this clock. The article shows that the claim that the speed of light in a vacuum is the maximum speed in the real world has no theoretical basis. In modern physics, such a doctrine has been adopted as a result of an overinterpretation of the mathematics on which the Special Theory of Relativity is based. The presented model shows how, using atomic clocks, it may be possible to determine the movement in relation to the universal frame of reference in which electromagnetic signals propagate. This article contains only original research.