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
Mesoamerican calendars Mesoamerican calendars Mesoamerican calendars are the calendrical systems devised and used by the pre-Columbian cultures of Mesoamerica. Besides keeping time, Mesoamerican calendars were also used in religious observances and social rituals, such as for divination. The existence of Mesoamerican calendars is known as early as ca. 500 BCE, with the essentials already appearing fully defined and functional. These calendars are still used today in the Guatemalan highlands, Veracruz, Oaxaca and Chiapas, Mexico. Among the various calendar systems in use, two were particularly central and widespread across Mesoamerica. Common to all recorded Mesoamerican cultures, and the most important, was the 260-day