While the article in general is great, the author’s assumption of one true time is rather cute :). At the very least, there are: - the actual number of second

While the article in general is great, the author’s assumption of one true time is rather cute :). At the very least, there are: - the actual number of seconds that passed since the epoch, i.e. the number a perfect egg timer would show if you had set it off at 12 AM on 1970-01-01. - International Atomic Time (IAT), the closest thing to the aforementioned egg timer we currently have (though with some offset, naturally). - Terrestrial Time (TT), which is 32.odd seconds ahead of IAT, apparently for historical reasons. - Universial Time (UT<timezoneoffset>), which is supposed to be the solar time at one particular location, Greenwhich for UT1. - Coordinated Universal Time (UTC), probably the closest thing to The One True Time, which jumps around merrily depending on the rotational speed of Earth, trying to keep days of 86400 SI seconds. Oh, and we’re not even considering relativistic effects here.