Why is there a leap on the calendar of 1988?

Leap year means leap year. It's convenient to remember time like leap month. A leap of four years; Never leap in a hundred years, and then leap in four hundred years. (1988 divisible by 4 is a leap year. )

The establishment of leap year is to make up for the time difference between the number of days in a year caused by man-made calendar regulations and the actual period of revolution of the earth. The year to make up for the time difference is leap year.

Leap years include years with leap days in Gregorian calendar or summer calendar.

A leap year has 366 days.