The Mayan calendar is significant as it reflects the complex astronomical knowledge and cultural practices of the ancient Maya civilization. One of its most famous features is the Long Count calendar, which measures time over vast periods and was used to predict celestial events and important dates in their society. The calendar is often associated with the December 21, 2012, phenomenon, which some interpreted as a prophesied end date, leading to widespread interest and misunderstanding. However, the calendar also illustrates the Maya's sophisticated understanding of cycles, timekeeping, and how these beliefs were integrated into their agriculture, religion, and social order.