Answer by
saurabhp (158)
12 a.m refers to midnight. 12 p.m. refers to noon. At each of the hours of 12, the a.m. changes to p.m. or the p.m changes to a.m. In the morning, think of 11:45 a.m. When the clock strikes 12, it changes to 12 p.m. After 11:45 p.m, when it's 12, it becomes 12 a.m.