What is time?
is a measurable period during which an action, process, or condition exists
or continues. It is often referred to as the fourth dimension, along with
the three spatial dimensions. Time as a unit is any particular time interval,
used as a standard way of measuring or expressing duration.
is approximately the period of time during which the Earth completes one
rotation around its axis.
is a unit of time conventionally known as
1/24 of a day
Since it varies between seasons, it is made constant by defining it to be
3600 atomic seconds