why the months vary in number of days?
99578
The length of the months is an arbitrary invention of humans.  Look at the names - SEPTember, OCTober, NOVember, DECember = 7th, 8th, 9th and 10th month?  Augustus Caesar took a day from FEB to add to AUG when he named AUG after himself.
522488
Possibly because 28 x 13 = 364.\n\nTo keep the years on an even keel, you need to have approximately 365 and 1/4 days in each year, which is why we have 365 days for 3 years running, and then the fourth year is 366 days. \n\nIn other words, there are 13 lunar cycles, plus 1 or 2 extra DAYS in a whole year - with a year being 4 seasons - so how would you deal with that if you were creating a 13 month calendar? Everything would end up out of sync! You would end up with a year that had 14 lunar cycles in it...!
611884
Jason M - That has to do with months, not weeks.\n\nThe 7 day week is because of creation.
883836
i couldn't tell you about years having the same dates onthe same day, but if you look at february and march, they have the same 28 dates/days for the first 28 days, except on leap years...how do i know.....a leap year mean having to wait an extra day for my birthday... :(  so you usually don't even have to change your claendar to march! spiffy huh?
606605
It's not different months, it's times of the months. This is because the of the moon's position in relation to us. The moon always faces us with the same side but that is not always the lit side. When it is a full moon, the sun light is reflecting off of "our" side of the moon. In a new moon, it is reflecting off of the other side.
366634
It gives us our months of the year
353316
There are 28 days in February because February was the low month on the totem pole. \nOriginally, the Roman calendar had 12 months of 29 or 30 days, beginning in March, with an extra (intercalary) month thrown in every other year to get things back in sync with the seasons. Unfortunately this led to abuses, as officials added or dropped intercalary months to extend their time in office or to hasten elections. \n\nSo in about 45 BC, Julius Caesar, who by now had made himself dictator of Rome, established a 365-day calendar with leap years. For reasons unknown to me but which seemed good to him at the time, he decided that instead of having five months with 31 days and seven with thirty, he would only allow February to have 30 days in a leap year. He incidentally renamed the fifth month, Quintilis, after himself (Julius, or July). \n\nJulius' adopted son and heir, Octavian, gained control of the state a few years after Julius' assassination in 44 BC. Octavian ruled so well that the Senate granted him the name of Augustus, and after his death he was formally deified by the Senate. As part of this, the month Sextilis following July was named August, just as Augustus had followed Julius as leader of the State. But since the month now named after the God Augustus had only 30 days, another day was taken from poor February and given to August. \n\nIt sounds silly, but that's the way it was.
623290
It is because you are trying to make a round peg fit into a square hole.\n\n7 x 4 = 28 x 13 lunar months = 364 days, \nbut there are 365 days in a regular year. \nThen in order to fit into the Earth's rotation around the Sun every 4th year we have to add an extra day.\nPlus occasionally we have Leap seconds too.\nConfused?
131949
Our version is a bit different.\n\n30 days has September, April, June, and November.\nAll the rest have 31\nExcept February \nWhich has 28 Days clear \nAnd 29 each Leap Year.\n\nMondays child is fair of face,\nTuesdays child is full of grace,\nWednesdays child is full of woe,\nThursdays child has far to go,\nFridays child is loving and giving,\nSaturdays child works hard for his living,\nAnd the child that is born on the Sabbath day\nIs bonny and blithe, and good and gay.
375333
I'm not sure but this might be a good start:\n\nhttp://en.wikipedia.org/wiki/Category:Months
1053014
August was named in honor of Augustus. The month reputedly has 31 days because Augustus wanted as many days as Julius Caesar's July. Augustus placed the month where it is because that is when Cleopatra died. Before Augustus renamed August, it was called Sextilis in Latin, since it was the sixth month in the Roman calendar which started in March.
182927
because it is not a monthly cycle.  it happens every 28-30 days and hence it will overlap a "monthly" period of time
530274
In the Gregorian calendar, February is the 2nd month of the year. However, the gregorian calendar is adopted from the Roman calendar, where febuary was the LAST month to be added, since in the Roman calendar, the year originally begins in march. \n\nTherefore, February contains the residual number of days after the previous 11 months (march to jan) has accorded their fixed number of days. Hence, when it's a leap year, the extra day is added to february.\n\nYou may also then ask why is it that July and August had 31 days each, when they are suppose to be alternated between 30 and 31 days? Rumor has it that it is so because Augustus Caesar (August is the month to commemorate him) did not want July (in commemoration of Julius Caesar) to have more days that August.
480279
because it relies to the events which can't be measured metrically anyway. Weeks follow the approximate lunar circle, there's 365 days in a year etc.\n\nalso, imagine we would divide a day into 100 hours. 1 hour would last only 14 minutes, which would be way too few and confusing. \nIf we divided a day into 10 hours, an hour would last 2 hours and 64 minutes. this would probably be too long, and we wouldn't have enough hours to properly determine a time of day...\n\nAn hour was determined as 1/4 of the time when the shadow of a pole travels a 60 degree angle or something... i THINK. I might be wrong on this, high school phisics is a LONG time ago. \nAnyway, it was old Sumerians or Babilonians who determined it like that and ever since it wasn't changed. We're too used to these units now, we can't just change them without causing a massive MESS :D
610941
6.month. 6. day. year.06. ?
819146
As you know a year is a full rotation of earth around the sun and initially month was the full rotation of moon around earth. Sumerians created their first calendar using this information. The problem with this is that a full rotation of moon is 29.5 days then 12 months make just 354 days. This is shorter than a year. Therefore, a synchronization was needed. In order to be able to synchronize their calendar people added another 13th month in every three years. However a standardization could not be achieved, different people added the 13th month at different times. This created a lot of problems especially for trade and contracts. As a result of this experience people thought that something is bad about 13 and they changed their calendar in such a way that months are no longer equal to the full rotation of moon around earth. There are still some calendars with a month equal to the full rotation of moon. For example, "honey moon" is a saying from those old days, because it was the tradition that father of the bride provided a fermented honey drink to the groom for a full month after the marriage.
979227
Remember, our bodies are not machines that work exactly the same way every month.  No one is exactly perfectly every 28 days all the time - I have had a few times where I didn't have a period one month and I wasn't pregnant, then the next month there is was again.\nAnd sometimes 2 in one month (our bodies don't know how to read a calendar, so what is a month on paper isn't necessarily a month in our systems with hormones, stress, diet, and so many other things affecting everything about us.