Mesoamerican Long Count calendar 18. Thus 0.0.1.0.0 does not represent 400 days, but rather only 360 days and 0.0.0.17.19 represents 359 days. The name "b'ak'tun" was invented by modern scholars. The numbered Long Count was no longer in use by the time the Spanish arrived in the Yucatán Peninsula, although unnumbered k'atuns and tuns were still in use. Instead the Maya were using an abbreviated Short Count. Long Count dates are written with Mesoamerican numerals, as shown on this table. A dot represents "1" while a bar equals "5". The shell glyph was used to represent the zero concept. The Long Count calendar required
Adoption of the Gregorian calendar No. 28 of Month 1 () On the other hand, people never call dates on the Chinese calendar as "No. "dd".", which avoids any possible ambiguity. When referencing dates before the introduction of the Gregorian calendar in 1582, the official Chinese calendar may either inherit the issues with earlier calendars to be historically correct or follow the proleptic Gregorian calendar if so specified. The Islamic calendar is a lunar one, so that there are twelve lunar months in a year of 354 or 355 days, being 11 days shorter than a solar year. Consequently, holy days in Islam migrate around