Epoch timestamp is a unit of measurement for time. It is the number of
seconds elapsed since the countdown has started.
Beginning epochs per system:
macOS - January 1, 1904
Windows - January 1, 1601
Unix - January 1, 1970
1
0
N
date +"%T.%6N" # returns the current time with nanoseconds rounded to the first 6 digits, which is microseconds
# In general, every field of the `date` command's format can be given an optional field width..