By early Iron Age times (ca. 1000 B.C.), literacy had spread into South Arabia via the revolutionary new alphabetic script. Originating in the South Sinai by 1500 B.C., its ease of use made vast inroads in both areas previously illiterate as well as established writing centers (Egypt, Levant, Mesopotamia). Such was the case in MSAL areas. This alphabetic script (in a format sometimes called Thamudic), came into use by the late first millennium B.C. It was not replaced until the early Arabic Kufic script arrived ca. 650 A.D.