Task
 
Choose popular date libraries used by your language and show the   epoch   those libraries use.

A demonstration is preferable   (e.g. setting the internal representation of the date to 0 ms/ns/etc.,   or another way that will still show the epoch even if it is changed behind the scenes by the implementers),   but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.

For consistency's sake, show the date in UTC time where possible.



Related task

   Date format


 
object cal = Calendar.ISO->set_timezone("UTC");
write( cal.Second(0)->format_iso_short() );
 