and AD stands for "Anno Domini," which is a Latin term meaning "in the year of the Lord".
https://search.brave.com/search?q=what+do+the+abbreviations+AD+and+BC+mean+with+respect+to+years&summary=1&conversation=f96f04da79019ea13810ef
It is used to denote years following the traditionally reckoned birth of Jesus Christ. BC stands for "Before Christ" and refers to the years before the birth of Jesus Christ.
These abbreviations are part of a system that counts years from the birth of Jesus, with AD being used for years after his birth and BC for years before his birth.
So a ragtag group of fishermen following a man who claimed to be the Messiah, but who was crucified by the Roman authorities at the behest of the Jewish leaders were persecuted and killed (all except for St. John, who was exiled on the island of Patmos) by the greatest military power on earth and yet they were able to convince others of the veracity of their claims, despite those who followed them also being fed to lions or burned on poles or thrown in dungeons & tortured and this "new" religion grew and endured for thousands of years and indeed split time in half.
There are currently ongoing miracles around the world that science cannot explain and you can go and visit yourself.
There is FAR more historical evidence than you realize, or at least that you will not admit.