- several decades ago the new machine time system has been born: unix time
- the first second started at 1 jan 1970 of the the old time
- since when its is the only format in which computers account time
- satoshi learns how to prove unix time more when decade ago
- in aos we count time from the moment of 0 second of unix time
- time after this moment is called: machine time or mt
- any previous time is marked with minus and is called: before machines or bm