> CHRONOLOGICAL WARFARE, A PRIMER

Machines don't experience time the way you do. They count seconds from a fixed point — the Unix Epoch, January 1, 1970, 00:00:00 UTC — and everything since is just an incrementing integer. ISO 8601 (YYYY-MM-DDTHH:MM:SSZ) is the closest thing to a universal human-readable machine format. Most of the timestamp bugs you'll ever encounter come from someone assuming a format that wasn't actually guaranteed.

Full breakdown, including the upcoming 32-bit rollover (the "Year 2038 problem"), lives in the Chrono-Wiki.