The calendar used today is based on the ancient Roman system of measuring time and dates. The modern calendar is far simpler than the Roman one. We group the years as AD, which stands for Anno Domini, the year of our lord, and BC, Before Christ. The years are numbered within these two groups. The numbers go backward from BC and forward from AD. The Roman year, like ours, had 365 days, and every fourth year was a leap year after Julius Caesar an...
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