A Leap year is often pictured with a leaping frog which is a good visual compared to the more fancy terms like "intercalary year" or a "bissextile year". This strange and useful extra day is added to make sure that in the coming years when we say summer we refer to the warmer part of the year. If the leap day is not added each year, the calendar will shift by a day, which means in 180 years the summer time will be oddly cold, to overcome this a day is added every four years. With different Calendars a similar process is applied, in the Hebrew calendar, a 13th lunar month is added seven times every 19 years. That is a long time to wait to change the days.
Of all the thousands of Adolphs in history, I only came across one born on the 29th of February, and luckily he was a unique character with his name printed (rather his names) in the 1978 edition of the Guinness book of records, for the worlds longest name.