12 hour timekeeping method uses "morning", "morning" and "morning" to describe a day from 0: 00 to noon 12, and uses "afternoon", "evening" and "night" to describe a day from noon 12 to noon 12.

The 24-hour clock method starts at night 12 (0: 00) and ends at noon 12. One turn of the hour hand is 12 hours, and one turn from noon 12 (0: 00) is also 12 hours.

In daily life, the 12 hour timekeeping method is often used, while the 24-hour timekeeping method is mainly used for timekeeping in posts and telecommunications, transportation, broadcasting, television and other departments. In a day, the clockwise hand goes twice, which is ***24 hours.

The timing method from 0: 00 to 24: 00 is 24: 00, and the timing method from 0: 00 to 12 is 12. According to this timing method, it is 1 3: 00 in the afternoon, 15:00 in the afternoon, 24:00 in the afternoon 12 and 0:00 the next day.

At the same time, the hourly value range of 12 is 1- 12, and the minutes and seconds are constant, starting from midnight 12 in the morning, that is, am; The afternoon starts at noon 12, which is PM. For example, 1 1:00 am corresponds to1:00am, and 19:00 pm corresponds to 7:00PM.