Believe it or not, some people think that the end of the world will happen on December 21st, 2012. Where does this belief come from? Well, its origin is the ancient Mayan calendar, which regards the 21st of December as the end date of a 5,125-year-long-cycle. That’s a fact. But what does it really mean? And what will really happen on that date? Well, that has been the subject of many different interpretations.