en.wikipedia.org/wiki/Leap_year

A leap year is a calendar year containing one additional day added to keep the calendar year ..... One reason for this rule is that Yom Kippur, the holiest day in the Hebrew calendar and the tenth day of the Hebrew year, now must never be ...

www.timeanddate.com/date/leapyear.html

Feb 29, 2016 ... A leap year has 366 days, as opposed to a common year, which has 365. We add a leap day – February 29 – nearly every four years.

www.quora.com/What-is-the-main-reason-for-leap-year

TL;DR;. The simple reason for leap year is that the earth revolves around the sun in approximately 365.25 days, and so to make sure that a calendar year is the ...

www.infoplease.com/leap-year-explained

A common year has 365 days and a leap year 366 days, with the extra, or intercalary, day designated as February 29. A leap year occurs every four years to ...

metro.co.uk/2016/02/26/the-science-behind-why-we-have-a-leap-year-every-four-years-5720043

Feb 26, 2016 ... 2016 is a leap year, meaning we have one extra day on February 29, but ... why February drew the short straw, there's a (slightly unfair) reason.

www.history.com/news/ask-history/why-do-we-have-leap-year

Feb 19, 2014 ... Nearly every four years, we add an extra day to the calendar in the form of February 29, also known as Leap Day. Put simply, these additiona...

www.slate.com/blogs/bad_astronomy/2016/02/29/the_math_behind_leap_years.html

Feb 29, 2016 ... Why do we have leap years? The math behind this is interesting, and has to do with Earth's spin and orbit around the Sun.

www.wired.com/2012/02/why-is-there-a-leap-year

Feb 29, 2012 ... Really, the question should be: why aren't there even more leap years? Let me start with the basics. A Year. What is a year? To a child, this may ...

www.mathsisfun.com/leap-years.html

Leap Years are any year that can be evenly divided by 4 (such as 2012, 2016, etc). not, except if it can be evenly divided by 100, then it isn't (such as 2100, 2200 ...