A clock with hands (an analogue clock) shows us the numbers 1-12. There are 24 hours in one day, so we measure time by splitting the day into two halves. The first 12 hours of the day, from ...
O'clock is a way of telling the exact hour on a clock. We say "o'clock" when the minute hand (the long hand) points to the number 12 on the clock. When the minute hand points straight up to 12 ...