The
Hijri year or
era is the
era used in the
Islamic lunar calendar, beginning its count from 622 , the year of the migration of
Muhammad and his followers from
Mecca to
Yathrib (later
Medina), an event known as the
Hijra. It is denoted in
Arabic with a
hāʾ , the first letter of Hijra. It is denoted in English by the abbreviation
AH, which follows the format of the
Dionysian era in representing a
Latin phrase. means "in the year of the Hijra" and should technically precede dates in the manner of . More commonly, it is placed after the year.