Since, technically, a year consists of 365 days and approximately 6 hours, every four years these hours amount to a full day. In order to synchronize the Gregorian calendar with the astronomical year, a leap day, February 29, is added to the 28-day month once every four years. As such, leap years are always evenly divisible by four. Persons born on a leap day are called “leaplings,” and, contrary to popular myth, they do age during non-leap years. What opera centers on a leapling and his aging? Discuss
Source: The Free Dictionary