Do you know the truth about leap year? Take our quiz - CNET

You probably know that 2016 is a leap year. But do you know why?

Leap years are needed to align our mode-day 12-month calendar year with the solar year, or the length of time it takes the Earth to rotate around the sun. The solar year is just a few hours longer than 365 days. If we didn't add an extra day every four years, we'd end up being six hours shy every year and our seasons would get out of sync with the calendar.

Leap years generally show up once every four years and bring an extra day with them, in February. This day might not seem like a big deal unless you were bo on February 29, otherwise known as a leap day. People who came into the world on that day are called "leaplings," and during non-leap years, they usually celebrate their birthdays on February 28 or March 1. But hard-core leaplings only blow out the candles on February 29.

How familiar are you with leap years and all that's associated with them? Hop right in and test yourself with our quiz to see how much you know about notable leaplings and other facts related to leap year.