It will update your system clock time, synchronizing it with atomic clocks through the Internet.

该软件将更新你的系统时间，通过因特网使用原子时钟同步你的系统时间。

youdao

While you and I know what an hour is, the people who invented the word had no clocks and for them an hour was not so much a length of time as a milestone through the course of the day.

虽然你我都知道hour是什么意思，但在发明这个词的年代，人们还没有时钟，hour并不完全指一段时间的长度，而更像是一天当中的某个时间点。

youdao

Then through the use of GPS-based reference clocks at each tower (for both time and frequency), the signals are synced so each can emit a perfect copy of both signal and symbol data.

ENGADGET: blogger-avatar

My first assumption was that there was an electrical fault, but as the time settled on 5 minutes past one, I suddenly realised that it was "'clocks going back time" ...and I would have to sit through that whole hour again!

BBC: A mean time for doctors