CFGS GT2/AV2 M5 RECURSOS TURÍSTICS 3.1. Termes artístics A quin tipus de datacions fa referència les següents abreviacions: aC / dC : abans de Crist / després de Crist BC / AD: before Christ / Anno Domini There is noyear zero in this scheme, so the year AD 1 immediately follows the year 1 BC. This dating system was devised in 525, but was not widely used until after 800. Traditionally, English followed Latin usage by placing the abbreviation before the year number for AD. Since BC is not derived from Latin it is placed after the year number (for example: AD 2013, but 68 BC). However, placing the AD after the year number (as in "2013 AD") is also becoming common usage AUD: ad urbe condita (Foundation of Rome: 753 BC) The Gregorian calendar is the most widely used civil calendar in the world.[Note 1] It is named after Pope Gregory XIII, who introduced it in October 1582 The Anno Domini era was introduced in 525 by Scythian monk Dionysius Exiguus (c. 470–c. 544), How he arrived at that number is unknown. AEC / EC abans era comuna / era comuna (cat/esp) (a.e.c. - a.E.C / e.c.) a. de la n.e. / de la n.e. abans de la nostra era / de la nostra era (cat) BCE / CE before common era / common era E.V: era vulgaris Common Era or Current Era (CE) is one of the notation systems for the world's most widely used calendar era – an alternative to the Dionysian AD and BC system. The era preceding CE is known as before the Common Era or before the Current Era (BCE), whereas the Dionysian era distinguishes eras using AD (anno Domini, "[the] year of [the] Lord") and BC ("before Christ"). Since the two notation systems are numerically equivalent, "2018 CE" corresponds to "AD 2018" and "400 BCE" corresponds to "400 BC".[a] Both notations refer to the Gregorian calendar (and its predecessor, the Julian calendar). The year-numbering system utilized by the Gregorian calendar is used throughout the world today, and is an international standard for civil calendars. BP (1950) : Before present AP (1950) : Abans del present Before Present (BP) years is a time scale used mainly in geology and other scientific disciplines to specify when events occurred in the past. Because the "present" time changes, standard practice is to use 1 January 1950 as the commencement date of the age scale, reflecting the origin of practical radiocarbon dating in the 1950s.