section_path: Abstract
section_name: Abstract
paragraph_text: The Hebrew calendar (Hebrew: הַלּוּחַ הָעִבְרִי), also called the Jewish calendar, is a lunisolar calendar used today for Jewish religious observance and as an official calendar of Israel. It determines the dates of Jewish holidays and other rituals, such as yahrzeits and the schedule of public Torah readings. In Israel, it is used for religious purposes, provides a time frame for agriculture, and is an official calendar for civil holidays alongside the Gregorian calendar.
  
  Like other lunisolar calendars, the Hebrew calendar consists of months of 29 or 30 days which begin and end at approximately the time of the new moon. As 12 such months comprise a total of just 354 days, an extra lunar month is added every 2 or 3 years so that the long-term average year length closely approximates the actual length of the solar year.
  
  Originally, the beginning of each month was determined based on physical observation of a new moon, while the decision of whether to add the leap month was based on observation of natural agriculture-related events in ancient Israel. Between the years 70 and 1178, these empirical criteria were gradually replaced with a set of mathematical rules. Month length now follows a fixed schedule which is adjusted based on the molad interval (a mathematical approximation of the mean time between new moons) and several other rules, while leap months are now added in 7 out of every 19 years according to the Metonic cycle.
  
  Nowadays, Hebrew years are generally counted according to the system of Anno Mundi (Latin: "in the year of the world"; Hebrew: מבריאת העולם, "from the creation of the world", abbreviated AM). This system attempts to calculate the number of years since the creation of the world according to the Genesis creation narrative and subsequent Biblical stories. The current Hebrew year, AM 5785, began at sunset on 2 October 2024 and will end at sunset on 22 September 2025.