Time?!(1)

What is time? How is it indicated and can the concepts about time in "the Tenet" and "Interstellar" be true? Humans first started measuring time from sticks in the ground. According to the length of the stick's shadow created during the day, time could be measured. The dozen being our ancestors' basis of counting they split the circle of time created by the stick's shadow into 12 parts which accounted for half of a day.

A different group counted numbers on the basis of 60, so they divided each part of the day into 60 parts twice.

Our Greek and Latin ancestors even called the sides of the head the "Temporal Region" because of its tendency to turn grey with time.