Know about Leap Year

 A leap year is a year that is evenly divisible by 4, except for years that are divisible by 100. However, years divisible by 400 are still leap years.

Definition

Leap years occur approximately every four years to synchronize the calendar year with the solar year, which is about 365.242 days long.

Frequency

Leap years have one extra day added to the calendar, making February 29 days long instead of the usual 28.

Extra Day

The purpose of leap years is to keep the calendar year aligned with the astronomical year, ensuring that seasonal events occur at the same time each year.

Purpose

The Julian calendar, introduced by Julius Caesar in 45 BCE, was the first to include leap years.

Julian vs. Gregorian

While most leap years follow the 4-year rule, there are exceptions. Years divisible by 100 are not leap years unless they are also divisible by 400. 

Exceptions

The concept of leap years has been around for thousands of years, with ancient civilizations such as the Egyptians and the Babylonians implementing similar systems 

Historical Significance

The Earth's orbit around the sun is approximately 365.242 days long, so an extra day is added to the calendar every four years to account for the fraction. 

Mathematical Explanation