Note that if a.m. or p.m. finish a sentence, as in The train arrives at 10 p.m.m., there is no need to set an additional time at the end. And for our last writing tip, since these abbreviations indicate an hourly relationship at noon, it is not necessary to use them in the morning, evening, night or clock. The 12-hour time convention is common in several English-speaking countries and former British colonies, as well as in other countries. This is an example of a duodecimal system. For more information about writing the time of day, see TIME OF DAY, ELAPSED TIME. Many American style guides and the NIST FREQUENTLY Asked Questions (FAQ) recommend that it be clearer to refer to "noon" or "12:00 p.m." and "midnight" or "12:00 p.m. midnight" (rather than "12:00 p.m.). m." and "12:00 p.m. . . m.
»). The NIST website states that "12 a.m. and 12 P.m. are ambiguous and should not be used. Unicode specifies code points for the symbols "a.m." and "p.m., which should only be used with Chinese-Japanese-Korean (CJK) character sets because they occupy exactly the same place as a CJK character: Ante meridiem is commonly referred to as AM, am, a.m., or A.M.; post meridiem is usually abbreviated to PM, pm, p.m. or P.M. Like many other sources, timeanddate.com am and pm, but the other variants are just as correct and widely used. If the 24-hour clock is used, a.m. and P.m. are useless and wrong. Some countries, including the United States, Canada and Australia, use the 12-hour format, including am and pm.
What do these abbreviations mean? Is it midnight or afternoon? There is a third, lesser-known abbreviation in this system: m. from the Latin merīdiēs means "noon" means noon. M. is rarely used and could confuse readers or listeners if you casually drop it in conversation or insert it into your writing; Noon is usually expressed at 12:00.m or 12:00 .m and midnight at 12.m:00 or 12:00 .m. This tutorial briefly covers the definition, examples, the difference between AM and PM, and other detailed information related to Anti Meridiem or AM. The complete form of the abbreviation AM is Anti Meridiem. Most countries in the world now use the system 24 hours a day. However, the 12-hour format, including am and pm, is officially used in a number of countries, including the United States, Canada (except Quebec), Australia, New Zealand, and the Philippines. P.m. is an abbreviation of post merīdiem, which – you guessed it – means "afternoon".
Never use a.m. or p.m. with the expression clock or with the words tomorrow, afternoon, evening or evening. In several countries, the 12-hour clock is the dominant written and spoken time system, especially in countries that were part of the former British Empire, for example, the United Kingdom, the Republic of Ireland, the United States, Canada (except Quebec), Australia, New Zealand, India, Pakistan, Bangladesh, Malaysia and Malta, and others also follow this convention. such as Egypt, Mexico, Nepal and the former American colony of the Philippines. However, in most countries, the 24-hour clock is the standard system used mainly when writing. Some countries in Europe and Latin America use a combination of both, preferring the 12-hour system in colloquial language, but the 24-hour system in written form and in formal contexts. In his book Mapping Time, E. G. Richards provided a diagram in which 12 a.m.
Noon and 12 P.m means. means midnight.  The main weakness of the 12-hour system is the widespread confusion as to which abbreviation to use for noon and midnight: neither time can logically be identified as before noon (on) or after noon (in the evening). For example, the time of midnight occurs exactly 12 hours after noon the day before and 12 hours before noon the next day. In Canada, these abbreviations are usually written in lowercase, with periods and without internal spacing. A protected space must be used between the time and the abbreviation a.m. or p.m. The term we associate with morning, a.m., is an abbreviation of the Latin expression ante merīdiem, which means "before noon". In spoken English, full hours are often represented by the numbered time followed by the clock (10:00 as ten o`clock, 2:00 as two hours).
This can be followed by the term "a.m." or "p.m.", although some expressions such as morning, afternoon, evening or night more often follow analogous terms such as clock, half three and quarter to four. O`clock itself can be omitted and an hour like four a.m. or four p.m. The minutes ":01" to ":09" are usually pronounced as oh one to oh nine (zero or zero can also be used instead of oh). The minutes ":10" to ":59" are pronounced like their usual numeric words. For example, 6:02 a.m. six oh two a.m can be pronounced, while 6:32 a.m. could be said six thirty-two a.m. Similarly, some American style guides recommend either clarifying "midnight" with other contextual cues, for example. B to specify the two dates between which it is located, i.e. not to refer to the term at all. For an example of the latter method, "midnight" is replaced by "11:59 p.m.
m. " for the end of a day or "12:01 p.m. a.m." for the beginning of a day. This has become common in the United States in legal treaties and for plane, bus or train schedules, although some schedules use different conventions. Sometimes, when trains run at regular intervals, the model may be interrupted at midnight by postponing the midnight departure by one or more minutes, para. B example at 23:59.m .m or 12:01.m .m.. In the morning. in the afternoon. in the evening and .
At night. Rider`s British Merlin Almanac for 1795 and a similar almanac for 1773 published in London used them.  Unlike English-speaking countries, the terms a.m. and p.m. are rarely used and are often unknown. Most other languages do not have formal abbreviations for "before noon" and "afternoon," and their users use the 12-hour clock only orally and informally. [Citation needed] However, in many languages, such as Russian and Hebrew, informal terms are used, such as "9 a.m." or "3 a.m." The natural day-night division of a calendar day is the basic basis for which each day is divided into two cycles. Originally, there were two cycles: a cycle that could be followed by the position of the sun (day), followed by a cycle that could be followed by the moon and the stars (night). This eventually evolved into the two 12-hour periods used today, one called "a.m." from midnight and the other called "p.m." from noon. Noon itself is rarely abbreviated today; but if so, it is designated by "m".  Minutes can be expressed as an exact number of minutes after the hour on the hour, indicating the time of day (e.B.
6:32 p.m.m. is "six thirty-two"). In addition, when expressing time with the formula "past (after)" or "until (before)", it is customary to choose the number of minutes below 30 (e.B 18:32.m. is conventionally "twenty-eight minutes before seven" and not "thirty-two minutes after six"). Some style guides suggest using a space between the number and abbreviation a.m. or p.m. [Citation needed] Style guides recommend not using a.m. and p.m. without prior time.
 One way to overcome this problem is to sacrifice accuracy for clarity. Your friend might ask you to be at the airport at 12:01.m April 13 or, if you mean the next midnight, at 11:59 p.m.m april 13. Alternatively, the 24-hour format could be used. Here, 0:00 refers to midnight at the beginning of the day, while 24:00 is midnight at the end of the day. To convert the time in or afternoon to the 24-hour format, use these rules: it is not always clear which times refer to "12:00 a.m." and "12:00 p.m." Among the Latin words meridies (noon), ante (before) and post (after), the term ante meridiem (a.m.) means before noon and post meridiem (p.m.) means afternoon. Since "noon" (noon, meridia (m.)) is neither before nor after itself, the terms a.m. and p.m. will not apply.  Although "12 m." has been proposed as a means of indicating noon, this is rarely done and does not resolve the question of how midnight should be displayed. The abbreviations a.m. and p.m. mean the Latin ante meridiem and post meridiem, which means before and after noon.
These abbreviations should only be used with numbers (e.B 9:00 a.m. or 9 a.m., not nine a.m.). The first mechanical watches of the 14th century, if at all, were displayed every 24 hours with the 24-hour analog dial, influenced by astronomers` familiarity with the astrolabe and sundial and their desire to model the apparent movement of the Earth around the sun. . . .