The Islamic, Muslim, or Hijri calendar (Arabic: التقويم الهجري at-taqwīm al-hijrī), known in the Western world by the Latin translation Anno Hegirae, is a lunar calendar consisting of 12 months in a year of 354 or 355 days. The year 1 of this calendar coincides with the year 622 CE, when Muhammad and his followers migrated from Mecca to Yathrib (now Medina) and established the first Muslim community (ummah), an event commemorated as the Hijra. It is used in Muslim countries to determine the proper days of Islamic holidays and rituals, such as the annual period of fasting and the proper time for the pilgrimage to Mecca. In everyday life of these countries the Gregorian Calendar is used. Rents, wages etc. are paid by the Gregorian calendar which is also used for agriculture, if no traditional solar calendars are used for this purpose, because a lunar calendar is not suited for agricultural work.