What is a leap year And when do they occur?

Answer 1

Dear,

Leap year.

Every fourth year (excluding years divisible by 100 but not exactly divisible by 400, e.g. excluding1900, including 2000), consisting of 366 days adding one day in February.

Answer 2

A leap year (or intercalary year) is a year containing an extra day (or, in case of lunisolar calendars, an extra month) in order to keep the calendar year synchronised with the astronomical or seasonal year. For example, February would have 29 days on a leap year instead of the usual 28. Seasons and astronomical events do not repeat at an exact number of days, so a calendar which had the same number of days in each year would over time drift with respect to the event it was supposed to track. By occasionally inserting (or intercalating) an additional day or month into the year, the drift can be corrected. A year which is not a leap year is called a common year. In fact, the Earth takes slightly under 365 1/4 days to revolve around the Sun.

In order to get a closer approximation, it was decided to have a leap day 97 years out of 400 rather than once every four years. This would be implemented by making a leap year every year divisible by 4 unless that year is divisible by 100. If it is divisible by 100 it would only be a leap year if that year was also divisible by 400.[2][3] So, in the last millennium, 1600 and 2000 were leap years, but 1700, 1800 and 1900 were not. In this millennium, 2100, 2200, 2300, 2500, 2600, 2700, 2900 and 3000 will not be leap years, but 2400 and 2800 will be. The years that are divisible by 100 but not 400 are known as "exceptional common years". By this rule, the average number of days per year will be 365 + 1/4 - 1/100 + 1/400 = 365.2425.


[edit] Leap year algorithms
Calculating leap years is simple, and is provided here by two different pseudocodes that determine whether a year is a leap year or not:

Standard
if year modulo 400 is 0 then leap
else if year modulo 100 is 0 then no_leap
else if year modulo 4 is 0 then leap
else no_leap
Vectorized
mask400 ← year modulo 400 EQ 0 ; this is a leap year
mask100 ← year modulo 100 EQ 0 ; these are not leap years
mask4 ← year modulo 4 EQ 0 ; this is a leap year
return ((mask4 and ~mask100) or mask400)
where ~ is the bitwise logical NOT operator. These algorithms are for a Proleptic Gregorian calendar, which include leap years before the official inception in 1582.

Answer 3

A leap year (or intercalary year) is a year containing an extra day (or, in case of lunisolar calendars, an extra month) in order to keep the calendar year synchronised with the astronomical or seasonal year. For example, February would have 29 days on a leap year instead of the usual 28. Seasons and astronomical events do not repeat at an exact number of days, so a calendar which had the same number of days in each year would over time drift with respect to the event it was supposed to track. By occasionally inserting (or intercalating) an additional day or month into the year, the drift can be corrected. A year which is not a leap year is called a common year. In fact, the Earth takes slightly under 365 1/4 days to revolve around the Sun.

Answer 4

A leap year is a year with one extra day inserted into February, the leap year is 366 days with 29 days in February as opposed to the normal 28 days.

the following rules decide which years are leap years:

1. Every year divisible by 4 is a leap year.
2. But every year divisible by 100 is NOT a leap year
3. Unless the year is also divisible by 400, then it is still a leap year.

Answer 5

in simple a leap year is a year which is divisible by 4. for example 2000 is divisible by 4 so its a leap year. here leap year ocuurs because in every 4 years a year will have 1 day added in its 365 days that makes it 366 days.

Answer 6

There are356 ,24 hour days in a year. Every 4 years one day is added on because of the time sequences, of extra time in years. One day is added in Feb. and 2008 is going to be a leap year.

Answer 7

ever heard of this

30 days haf september april june and november
all the rest have 31
except february alone which has 28 and 29 in each leap year

Answer 8

leap years come every fourth year of the calendar. It's to make up for a small discrepancy in our calendar in relation to our solar orbit. Rather than alter hours and minutes it's much easier to wait till it accrues to a day then it's added onto the shortest month.

Answer 9

A leap year is a normal year except there is one more day included in Feb and it occours every four years since every year consists of 3651/4 days.

Answer 10

Sharq is correct and that is why leap year comes every four years.