AM means before noon. This is the 12-hour period from midnight to noon. PM means after noon. It covers the 12 hours from noon to midnight. Using numbers from 1 to 12, followed by am or pm, the 12-hour clock system identifies all 24 hours of the day. We would like to show you a description here but the site won’t allow us. In particular, AM stands for ante meridiem, which translates into English as ‘before midday’. Meanwhile, PM is post meridiem and means in English ‘after midday’. These abbreviations are used to identify the time in the 12-hour clock format instead of using 24 hours. Separate the abbreviations from their number with a non-breaking space. The abbreviations stand for ante meridiem (before noon) and post meridiem (after noon) and are used strictly with twelve-hour time. Learn what is am and pm in the 12-hour clock system. AM means before midday and PM means after. Master time telling with simple rules and examples. Confused about AM and PM? ⏱️ Learn the difference, avoid common mistakes, and understand how 12-hour time compares to 24-hour format. The 24-hour clock is a method of telling the time in which the civil day runs from midnight until next midnight. The following numbers (used once in the same civil day) of hours are: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22 and 23, without AM nor PM. AM and PM are the abbreviated terms for Ante Meridiem and Post Meridiem respectively. While AM represents the time from midnight to 11:59 noon, and PM represents the time from 12 noon to 11:59 midnight. Originally there were two cycles: one cycle which could be tracked by the position of the Sun (day), followed by one cycle which could be tracked by the Moon and stars (night). This eventually evolved into the two 12-hour periods which are used today, one called a.m. starting at midnight and another called p.m. starting at noon. [1] Online shopping for from a great selection at All Departments Store.