15th century AH

A new issue of joint issues of postage stamps from the Arab collector, by Professor Khalid Al-Maamari, entitled "The Fifteenth Century" Hijri. The book documents an important stage in the history of humanity and the Islamic nation, as it highlights two important points: the first is the migration of the Prophet Muhammad, peace and blessings be upon him, from Mecca to Medina, and the other point is the adopted Islamic calendar, which began with the Prophet’s journey from Mecca to Medina.

The Islamic lunar calendar, also known as the Hijri or Arabic calendar, is a lunar calendar, meaning it relies on the moon's cycle to determine the months. It consists of 12 lunar months in a year of either 354 or 355 days. Muslims use it primarily to determine the month of Ramadan, the sacred months, the Hajj season, and the major holidays.