A leap year, where an extra day is added to the end of February every four years, is down to the solar system’s disparity with the Gregorian calendar.
A complete orbit of the earth around the sun takes exactly 365.2422 days to complete, but the Gregorian calendar uses 365 days.
So leap seconds – and leap years – are added as means of keeping our clocks (and calendars) in sync with the Earth and its seasons.
The chances of having a leap birthday are one in 1,461.
People who are born on February 29 are referred to as “leaplings”, or “leapers”.
In non-leap years, many leaplings choose to celebrate their birthday on either February 28 or March 1, while purists stick to February 29 for the occasion.