What do you need to know about 12 and 24-hour clock?

The 12-hour clock is a time convention in which the 24 hours of the day are divided into two periods - midnight and afternoon. In Latin, they are designated as a.m and p.m. The first abbreviation means “ante meridiem” - translating to before midday, and the second one means “post meridiem” - translating to after midday.

The 12-hour time clock is used in the following countries: Canada (with the exception of Quebec), Australia, USA, New Zealand, and the Philippines. The 12-hour time clock is also used in the UK (together with the 24-hour clock), as well as in Brazil, Greece, Albania and France.

As far as other countries of the world are concerned, they use the 24-hour clock. Despite this, when talking informally people can still use the 12-hour clock , for example, they can write or say that it’s 10 o’clock in the evening instead of saying that it is 22:00.

12 and 24-hour clock

In addition, leading zeros of minutes and seconds, and in some cases hours, must be indicated in this time format. People had begun to use this timescale relatively recently - just a few centuries ago. It appeared alongside with the introduction of the metric measurement system. There is even a suggestion that 24-hour clock was introduced just to make the Anglo-Saxons mad.

One of the advantages of the 24-hour clock over the 12-hour clock is that the latter often causes linguistic errors and misunderstandings. Designations a.m. and p.m. can be somewhat confusing.

In legal documents and commercial contracts, the time is written as 11:59 p.m. - midnight, and 12:01 a.m. - beginning of the next day.