Millions of people around the world will celebrate their unique birthday today – February 29 - or Leap day.
Why do we have leap years? We’ve been taught that each year is 365 days because that's the length of time it takes the Earth to revolve around the sun.
In truth, it takes a little longer (365 days, 5 hours, 48 minutes and 46 seconds, according to most calculations) and that’s why leap years were instituted every four years to make up the difference.
There are, however, some exceptions to the four-year rule. We do not count a leap year if the year in question ends in a double zero (1900, 2100) unless the year can be divided by 400 (such as 2000), and then it is a leap year.