AM and PM are abbreviations used in the 12-hour clock system to distinguish between the two 12-hour periods of a day.
- AM stands for Ante Meridiem , a Latin phrase meaning "before midday" or "before noon." It refers to the time from midnight (12:00 AM) to just before noon (11:59 AM)
- PM stands for Post Meridiem , which means "after midday" or "after noon." It covers the time from noon (12:00 PM) to just before midnight (11:59 PM)
Noon (12:00 PM) is the dividing point between AM and PM, and midnight (12:00 AM) marks the start of the AM period. To avoid confusion, it is often recommended to say "12 noon" and "12 midnight" explicitly
. In summary, the 12-hour clock uses AM for the hours from midnight to noon and PM for the hours from noon to midnight, effectively splitting the 24-hour day into two halves
