The next 12 hours, from midday to midnight, are called pm. However, you can tell the time without saying am and pm. To do this you can use the 24-hour clock. The 24-hour clock always uses 4 digits.

The Bulletin of the Atomic Scientists said they’ve moved their “Doomsday Clock” to 89 seconds to midnight, the closest it has ever been. Earth is moving closer to destruction, a science ...