Global thinkers will have to use global time if they are ever going to keep their dates straight. The difficulty: the day starts at different hours for each of the world's 24 standard time zones; ...

Slide 1 of 2, A digital clock showing 4.15, Omi's party starts at quarter past 4. On a digital clock this is shown as 4:15. There are 15 minutes in quarter of an hour.

Physicists have created an atomic clock that relies on a fundamental link between time and mass. The researchers, at the University of California, Berkeley, say that the pulse of the clock is ...