عمار بن ياسر
By the age of Muhammad, there was already an Arabian lunar calendar, with named months. Likewise, the years of its calendar used conventional names rather than numbers: for example, the year of the birth of Muhammad and of Ammar ibn Yasir (570 CE) was known as the "Year of the Elephant". The first year of the Hijra (622-23 CE) was named the "Permission to Travel" in this calendar.