[{TableOfContents}]

!![Overview Dates Time And Calendars]
Some information on [Overview Dates Time And Calendars].

! [Microsoft TIME]
[Microsoft TIME] is different.

! [UUID]
The [timestamp], as used in the [UUID] [RFC 4122] is a 60 bit value, representing the number of 100 [nanosecond] intervals since 15 October [1582|Year 1582] 00:00:000000000
This guarantees that there would be no duplicates in UUID until 3400 AD. (Then What? ;-) )

! [Unix Time]
[Unix Time] is a [NumericDate]

! [OpenVMS]
[OpenVMS], it's 00:00:00 of November 17, [1858|Year 1858] (base date of the [United States Naval Observatory]'s ephemerides)

! Macintosh
Macintosh, it's the midnight beginning January 1 [1904|Year 1904]. ([MacOS Epoch])

[System time] is measured in [seconds] or [Tick] past the [epoch]. 

! [Google] Sheets
[Google] Sheets uses a form of [epoch] [date] that is commonly used in spreadsheets. The whole number portion of the value (left of the decimal) counts the days since December 30th [1899|Year 1899]. The fractional portion (right of the decimal) counts the time as a fraction of one [day]. For example, January 1st [1900|Year 1900] at noon would be 2.5, 2 because it's two days after December 30th, [1899|Year 1899], and .5 because noon is half a day. February 1st [1900|Year 1900] at 3pm would be 33.625.

Note that Google Sheets correctly treats the year [1900|Year 1900] as a common year, not a leap year.! Interesting Links:
* [Epoch (reference date)|http://en.wikipedia.org/wiki/Epoch_(reference_date)]
* [Java Dates Timezones And Calendars]
!! More Information
There might be more information for this subject on one of the following:
[{ReferringPagesPlugin before='*' after='\n' }]