Religion: Calendar
The Mayans used three principal systems of measuring time. These systems
were a year of 365 days, a year of 360 days, and a period of 260 days.
The Mayan priests used these systems to help
calculate days that were beneficial to the society. In addition, important
religious ceremonies were based upon the priests' calculations.
The year of 365 days was called a haab. Each day was called a kin. The
Mayan times are almost entirely based on increments of twenty. Hence, twenty
kins made a uinal.
The haab was divided into 18 uinals and a period of five days. Theses days
were considered to be extremely unlucky for the Mayans.
The tun was the name of the 360 day system. The five unlucky days of the
haab were omitted in order to have just 360 days.
The 260 day calendar was called the tzolkin. The tzolkin was considered
the sacred year. It was the tzolkin that governed any Mayan's religious
and ceremonial life. A Mayan's birthday would correspond to a day of the
tzolkin.
The tzolkin was measured as a succession of 260 days and not as a series
of months. In this system, twenty Maya day names were combined with numbers
1 thru 13. A new tzolkin began only when every combination of days and numbers
had occurred.
The tzolkin was combined with the haab to form a period known as the Calendar
Round. A Calendar Round was a period of 52 years of 365 days.
The dates were numbered and shown according to the Mayan system of writing.
Glyphs of days
Glyphs of the months
Glyphs of the nine Mayan periods