am and pm meaning

Converting AM/PM to 24 Hour Clock. Add 12 to any hour after Noon (and subtract 12 for the first hour of the day): For the first hour of the day (12 Midnight to 12:59 AM), subtract 12 Hours. Examples: 12 Midnight = 00:00, 12:35 AM = 00:35. From 1:00 AM to 12:59 PM, no change. Examples: 11:20 AM = 11:20, 12:30 PM = 12:30. drama moon ga young and kim seon ho