“AM” stands for Ante Meridiem, it’s a Latin phrase that means “before noon,” and “PM” Post Meridiem means “after noon.” You should avoid the expression “12:00 PM” to designate noon, not only because it is incorrect, but because it can be confused with midnight . The same goes for “12:00 AM.” The correct will be “twelve noon” when you want to designate a precise time.
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