Early Macs normally had their clocks synced manually, until System 8.5 introduced support for NTP. That later switched to a proprietary service, timed, in macOS 10.13 High Sierra.
NTP
How to ensure your Mac’s clock and time is as accurate as possible, what can cause problems, and how it works using the timed daemon, as revealed in the log.
High Sierra has done away with the ntpd daemon for keeping your Mac’s clock in sync with a standard time server. This now works as in iOS, using the timed daemon.
Time should be universal, simple, and precise. Not in computers, though. Given enough clocks, it can behave oddly at times.
I have got lost, and ended up trying to set these in the Language & Region pane. Help!
How can we keep our Macs synchronised to the same time?
Like the moth which flies miles to contact an irresistible lantern, only to die in its flame, the C languages continue to draw programmers to their nemesis.
Time is central information for many functions on your Mac. This article explains the Network Time Protocol, and how it keeps time in OS X.
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