Question

how are the dates calculated in history

Answer 1

B.C. refers to "Before Christ," and the initials, A.D., stand for Anno Domini, which is Latin for "In the year of our Lord." This system was devised by a monk in the year 525. A more recent system uses B.C.E. which stands for "Before the Common Era" and C.E. for "Common Era."

Answer 2

CE and BCE
centuries
millennia....
mark me as BRAINLIEST......
follow me