Leap day and leap year.
Today is February 29th, 2008. If we look at the calendar, we will see that this month has five Fridays. In fact, February 2008 begins and ends on a Friday.
Today is the date that occurs only once in every four years. It is called a leap day.
With this additional day, 2008 will have 366 days. A leap year always consists of 366 days, whereas other years, called common years, have 365 days.
Why are leap years important? Leap years are needed to keep our calendar in alignment with the earth's revolutions around the sun. It is believed that the Egyptians were the first to come up with the idea of adding a leap day once every four years in order to keep the calendar in sync with the solar year. Later, the Romans adopted this solution for their calendar, and they became the first to designate February 29th as the leap day. There is an exception, though. Century years are NOT leap years, unless they can be evenly divided by 400.
The next leap year will be 2012.