What’s so special about this day that comes across
every fourth year? Well, to understand why there’s
a 366th day every four years, let’s look at the
astronomical aspects of an earth-year.

Most of us know that a year consists of 365 days. But the truth is that the earth year is exactly 365.2425 days thus making it necessary to have an additional day every 4 years. Those years are called leap years.

There’s one specialty though: Although the leap year occurs every fourth year, the rather odd number makes it necessary to drop the 366th day at the beginning of every century that is not divisable by 400. Thus we had February 29th in the year 2000 but not in the year 1900.

So what about people that are born on February 29^th? Do they have a birthday only every four years? Of course not! Some celebrate their birthday either on February 28^th or March 1^st.