The hour is hr, abbreviated as H.

Minute is min, abbreviated as m.

Seconds is sec, abbreviated as S.

Hours, minutes and seconds are all units of time. The basic unit of the international system of time units is the second. Except leap second, one hour is generally equal to 3600 seconds, or 60 minutes, or 1/24 days. The time of human daily life is generally measured in hours. For example, the time in a day, for example, 8 am, is the eighth hour in a day.

The conversion relationship between hours, minutes and seconds is:

1 hr = 60min min (m) = 3600s.

Extended data:

The origin of "hour"

In ancient China, time was measured by the method of "dripping water from a copper pot", and day and night were divided into twelve hours. One hour is equivalent to two hours of western clocks. When clocks and watches were introduced to China from the west, people called an hour "striking time" in China and a new hour "striking time" in the west. Later, with the popularity of clocks and watches, the word "Da Shi" gradually disappeared, and "Shi" has been used to this day.

Before the founding of the Republic of China, the twelve earthly branches were used to measure time. The earthly branch not only represents the year, month and day, but also the time, and divides a day into twelve hours: Zi, Ugly, Yin, Mao, Chen, Si, Noon, Unfinished, Shen, You, Xu and Hai. After the founding of the Republic of China, the year, month, day and time were marked by the year of AD, while the lunar calendar in China was preserved. In AD, a day was divided into 24 hours, which was twice as short as the traditional 12 hour, so it was called an hour.

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