Intercalation
This is where another calendrical technique called “intercalation” comes in. Intercalation is the process of inserting or removing a unit of time measurement (like a day) into your calendar to get it to line up with whatever natural cycle off which you’re based.
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This Gregorian system of an intercalary day is well-known to us and we’re pretty used to it. But once you get out of the western mindset of “January - December” and accounting for all the other billions of people around the world who measure time differently, you realize some key things, and one of the big ones is that intercalation is not limited to days or seconds.
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The Japanese calendar is a prime example of not making assumptions about dates. While the days and months are all based on the Gregorian calendar, the year is measured from the day that the current emperor ascended to the throne. And when an emperor passes on, a new year begins the very next day, even if it’s not actually the Gregorian “new year”.
Previously: Falsehoods Programmers Believe.
