The Anno Domini year–numbering system was introduced by a Christian monk named Dionysius Exiguus in the 6th century.

Conception (egg fertilization) usually occurs on the day of ovulation if there is sperm around but may be within a day or two later if intercourse is delayed until then.

The calculator assumes that ovulation occurs 14 days before your next expected period, no matter the length of your cycle.

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The protocols and practices of dating, and the terms used to describe it, vary considerably from country to country and over time.

While the term has several meanings, the most frequent usage refers to two people exploring whether they are romantically or sexually compatible by participating in dates with the other.

With the use of modern technology, people can date via telephone or computer or meet in person.

This term may also refer to two or more people who have already decided they share romantic or sexual feelings toward each other.

What relatively new is that more and more countries and their educational institutions have officially replaced the traditional abbreviations AD/BC with CE/BCE.

England and Wales introduced the CE/BCE system into the official school curriculum in 2002, and Australia followed in 2011.

The ancient city of Pompeii, Italy, was founded around 600–700 Before Common Era (BCE) and was destroyed by a volcanic eruption of Mount Vesuvius in 79 Common Era (CE).©bigstockphoto.com/miropink Because AD and BC hold religious (Christian) connotations, many prefer to use the more modern and neutral CE and BCE to indicate if a year is before or after year 1.