Mesoamerican Long Count calendar the use of zero as a place-holder and presents one of the earliest uses of the zero concept in history. On Maya monuments, the Long Count syntax is more complex. The date sequence is given once, at the beginning of the inscription and opens with the so-called ISIG (Introductory Series Initial Glyph) which reads "tzik-a(h) hab’ [patron of Haab' month]" ("revered was the year-count with the patron [of the month]"). Next come the 5 digits of the Long Count, followed by the Calendar Round (tzolk'in and Haab') and supplementary series. The supplementary series is optional and contains lunar data, for
Yoruba calendar clear(ly foreseen), calendar'. The traditional Yoruba calendar (Kojoda) has a 4-day week and 91 weeks in a year. The Yoruba year spans from 3 June of a Gregorian calendar year to 2 June of the following year. According to the calendar developed by Remi-Niyi Alaran, the Gregorian year 2015 AD is the 10,057th year of Yoruba records of time. With the British colonial and European cultural invasions, came the need to reconcile with the Gregorian calendar: Yoruba people also measure time in seven days a week and 52 weeks a year. Note: since there are thirteen months in the Youruba