What Does Leap Year Mean?

Leap year is basically a year that comprises of one extra day, week or month. This is in order to keep the calendar year synchronized based or with the help of astronomical or seasonal year. A year which generally does not comprise of any extra day is known as the usual common year. The best example for the leap year in the month of February one would generally see 29 days instead of the usual 28 days.
A person generally born on the 29th day of February is known as "leapling". On other usual years their birthday would either be celebrated on the 28th of February or even on the 1st of March.

A leap year is when the calender catches up for the four 1/4 days per year in a four year period.  It is on February 29th that the calender makes that adjustment. This happens because there are 365.25 days to a year. That is how long it takes the earth to make one cycle around the sun.