AM and PM time

Time

Time affects so much of what happens in our day-to-day lives. We wake up to our alarm clocks, we catch buses and trains that run to schedules and arrive at school or work at a set time. During our day, we operate to timetables and take breaks at certain times. We then leave to go home at certain times.

We measure time with either a 12-hour clock or a 24-hour clock. The traditional clocks are called analogue clocks and give us 12-hour time which uses am or pm. Digital clocks can either display 12-hour time or 24-hour time. A 24-hour clock does not display am or pm.

AM and PM time

The designation of 'am' and 'pm' with times in the 12-hour clock comes from the Latin language.

'Ante meridiem' (a.m.) means the morning hours, between midnight and midday (12 noon). 'Post meridiem' (p.m.) relates to the times after midday and before midnight - the afternoon and evening times.

A 24-hour clock does not need to display 'am' or 'pm'. The time of 6.30 is displayed on a 24-hour clock as 6:30 for morning and 18:30 for the afternoon. The 18:30 means 18 hours and 30 minutes since midnight.

12-hour and 24-hour time

24-hour clocks display time in four-digit notation. 8:15 am appears at '8:15' and is written as 0815 hours.

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