Anno Domini

Anno Domini (AD) is a Latin phrase meaning "In the year of our Lord," used to label years in the Gregorian calendar, which is the calendar most of the world uses today. It counts years starting from the birth of Jesus Christ, with AD years following that event. The system also includes BC (Before Christ) to denote years prior to his birth. While traditionally linked to Christian history, AD and BC are now commonly used in secular contexts to organize historical dates. Essentially, AD indicates years after a pivotal moment in history, serving as a chronological marker in historical records.