The Earth actually needs 365.25 days to make one complete orbit around the sun.
We gather all those .25s and make an extra day with them once every four years to keep the calendars up to date with the rest of the universe.
But that doesn't mean that today is also not without its special moments.
In some cultures, today is also known as Sadie Hawkins Day (originating in Al Capp's classic comic strip Li'l Abner), where it is socially acceptable for a woman to ask a man out on a date, or to propose marriage to them.
Although in Greece, it is considered unlucky to actually have the wedding on a leap year.
Fans of the television show Quantum Leap celebrate their favorite program
Before the milestone event known as the Crisis On Infinite Earths, DC Comics always said that Superman's birthday translated from the old Kryptonian calendar to February 29th on ours.
No word on when it occurs since all the cosmic resets that publisher has had.
So whatever is on your agenda, enjoy your extra day!