October 18, 2021
The Hijri calendar or the Islamic calendar is a lunar calendar that depends on the cycle of the moon to determine the months, and Muslims use it everywhere, especially in determining religious occasions. It was established by Caliph Omar Ibn Al-Khattab and made the migration of the Prophet from Mecca to Medina a reference for the first year in it, and this is the reason for calling it the Hijri calendar. Although the calendar was used in the era of Muslims, the names of the months and the lunar calendar were used from the days of ignorance. The 1st of Rabi’ al-Awwal was the beginning of the Hijri year But after a period of time and during the Umayyad era, two months were moved back for religious reasons, and Muharram 1 was considered the beginning of the Hijri year and the rest to this day. There are Arab countries that take the Hijri calendar as an official calendar to document official correspondence between the official state departments, but the general Arab peoples are in harmony and deal with the Gregorian calendar more than the Hijri calendar, except for the Kingdom of Saudi Arabia, which deals with the Hijri calendar on both the official and popular levels. The Hijri calendar consists of 12 lunar months, meaning the Hijri year is equal to approximately 354 days, specifically 354.367056 days, and the month in the Hijri calendar is either 29 or 30 days (because the apparent moon cycle is equal to 29.530588 days). Because there is an 11-day difference between the common Gregorian calendar and the Hijri calendar, the two calendars do not coincide, so this makes the conversion between the two calendars difficult.