Leap Year Explained
Why Does February Have a Leap Year Every 4 Years?

Learn why February has 29 days every 4 years and how leap years keep our calendar aligned with Earth's orbit around the Sun.

Unusual Odds in Leap Year
Understanding the Probability of 53 Mondays or Saturdays in a Leap Year

Explore the probability of having 53 Mondays or Saturdays in a leap year due to the extra day in February.