February 29 only occurs in years which are evenly divisible by four, although it's not quite that simple. Century years, eg 1800, 1900 are not leap years, unless unless it is also evenly divisible by 400. So just to confuse everyone, the year 2000 was a leap year.
10 facts about Leap Days:
https://topicaltens.blogspot.com/2016/02/29th-february-leap-day.html