12 | 12:00 pm
Timecountingsystem"Antemeridiem"redirectshere.Forthemeridian180°botheastandwestoftheprimemeridianinageographicalcoordinatesystem,seeantimeridian.The12-hourclockisatimeconventioninwhichthe24hoursofthedayaredividedintotwoperiods:a.m.(fromLatinantemeridiem,translatingto"beforemidday")andp.m.(fromLatinpostmeridiem,translatingto"aftermidday").[1][2]Eachperiodconsistsof12hoursnumbered:12(actingas0),[3]1,2,3,4,5,6,7,8,9,10and11.The12-hourclockwasdevelopedfromthesecondmillenniumBCandreacheditsmodern...
Time counting system
"Ante meridiem" redirects here. For the meridian 180° both east and west of the prime meridian in a geographical coordinate system, see antimeridian.The 12-hour clock is a time convention in which the 24 hours of the day are divided into two periods: a.m. (from Latin ante meridiem, translating to "before midday") and p.m. (from Latin post meridiem, translating to "after midday").[1][2] Each period consists of 12 hours numbered: 12 (acting as 0),[3] 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 and 11. The 12-hour clock was developed from the second millennium BC and reached its modern form in the 16th century AD.
The 12-hour time convention is common in several English-speaking nations and former British colonies, as well as a few other countries. There is no widely accepted convention for how midday and midnight should be represented: in English-speaking countries, "12 p.m." indicates 12 oclock noon, while "12 a.m." means 12 oclock midnight.[4][5][6]
Clock...