first established the 365-day year?
483741
The Mayans, about 2000 years before the Romans. \nThe Mayan year is called a Haab and is 365 days, which is also represented by the 91 step pyrimids (91steps x 4 sides = 364 + the top = 365)
272482
When the Sun was born. ;)  4.6 billion years ago.
900580
Lots of different ways.  There just needs to be an established convention.  And you need to make sure that no confusion can arise.\n\nYou can write it in a YYYYMMDD format, so today would be 20061107.\n\nYou can also express it in number of days since a certain date.  For example, you could make January 1, year 1 A.D. equal Day 1 and count from there.
668819
It doesn't.  It actually takes 365.2422 days, which is why every 100 years the leap year doesn't have an extra day.  Except for years than are evenly divisible by 400, they do.  (To make up for the 0.0022 extra.)  This most recently happened in 2000 and won't happen again until 2400.
436472
3000 years counting from when?
26411
a bit more than 365 days from now.
1101589
The world was created on the 23rd of October 4004 BC at exactly 9am.
686061
In the fourth century, Hillel II established a fixed calendar based on mathematical and astronomical calculations. This calendar, still in use, standardized the length of months and the addition of months over the course of a 19 year cycle, so that the lunar calendar realigns with the solar years. Adar I is added in the 3rd, 6th, 8th, 11th, 14th, 17th and 19th years of the cycle. The current cycle began in Jewish year 5758 (the year that began October 2, 1997). If you are musically inclined, you may find it helpful to remember this pattern of leap years by reference to the major scale: for each whole step there are two regular years and a leap year; for each half-step there is one regular year and a leap year. This is easier to understand when you examine the keyboard illustration below and see how it relates to the leap years above. \n\n \n\nIn addition, Yom Kippur should not fall adjacent to Shabbat, because this would cause difficulties in coordinating the fast with Shabbat, and Hoshanah Rabba should not fall on Saturday because it would interfere with the holiday's observances. A day is added to the month of Cheshvan or subtracted from the month of Kislev of the previous year to prevent these things from happening. This process is sometimes referred to as "fixing" Rosh Hashanah. \n\nNumbering of Jewish Years \nThe year number on the Jewish calendar represents the number of years since creation, calculated by adding up the ages of people in the Bible back to the time of creation. However, this does not necessarily mean that the universe has existed for only 5700 years as we understand years. Many Orthodox Jews will readily acknowledge that the first six "days" of creation are not necessarily 24-hour days (indeed, a 24-hour day would be meaningless until the creation of the sun on the fourth "day"). For a fascinating (albeit somewhat defensive) article by a nuclear physicist showing how Einstein's Theory of Relativity sheds light on the correspondence between the Torah's age of the universe and the age ascertained by science, see The Age of the Universe. \n\nJews do not generally use the words "A.D." and "B.C." to refer to the years on the Gregorian calendar. "A.D." means "the year of our L-rd," and we do not believe Jesus is the L-rd. Instead, we use the abbreviations C.E. (Common or Christian Era) and B.C.E. (Before the Common Era), which are commonly used by scholars today. \n\nMonths of the Jewish Year \nThe "first month" of the Jewish calendar is the month of Nissan, in the spring, when Passover occurs. However, the Jewish New Year is in Tishri, the seventh month, and that is when the year number is increased. This concept of different starting points for a year is not as strange as it might seem at first glance. The American "new year" starts in January, but the new "school year" starts in September, and many businesses have "fiscal years" that start at various times of the year. Similarly, the Jewish calendar has different starting points for different purposes. \n\nThe names of the months of the Jewish calendar were adopted during the time of Ezra, after the return from the Babylonian exile. The names are actually Babylonian month names, brought back to Israel by the returning exiles. Note that most of the Bible refers to months by number, not by name. \n\nThe Jewish calendar has the following months:\nHebrew English Number Length Gregorian Equivalent \n  Nissan 1 30 days March-April \n  Iyar 2 29 days April-May \n  Sivan 3 30 days May-June \n  Tammuz 4 29 days June-July \n  Av 5 30 days July-August \n  Elul 6 29 days August-September \n  Tishri 7 30 days September-October \n  Cheshvan 8 29 or 30 days October-November \n  Kislev 9 30 or 29 days November-December \n  Tevet 10 29 days December-January \n  Shevat 11 30 days January-February \n  Adar I (leap years only) 12 30 days February-March \n  A
25917
If you take leap years into consideration, the average year contains 525,948.766 minutes.  A year with just 365 days contains 525,600 minutes.
350635
The Mayan Calendar is probably where this came from.  I've been attempting to determine how that particular date came up.  Using the Gregorian calendar (our common), it is believed that the Mayans started counting to that date from what is called the "Birth of Venus", which is believed to be Aug 13, 3114 BC.  From that day, after "13 Baktuns", There would be a "re-awaking of time and space".  One Baktun is 144,000 days, or about 400 years (shy 80 minutes).\n\n13 Baktuns is 1,872,000 days.  There was no zero year between B.c. and C.e.   August 13, 3114, was actually, 3113 years, plus the number of days between Aug 13, and the end of 3114, which I believe, was 139.  It's important to understand the Gregorian calendar, in order to interpet the Mayan calendar (because these calculations are determined using the Gregorian calendar).  \n\nThe calendar was corrected on Aug 4, 1582 by pope Gregory, so from that point forward, and backward, the dates can be calculated using the Gregorian calendar.  At that time, it was determined that each four years would add one day, called a leap year, but on century years that are not divisible by 400 that would have been a leap year, the day (feb 29) would not be added.  But, on century years that are divisible by 400, there would be a day added, a leap year, as 2000 was.\n\nAnyway, I could go further here, but that date is about a year off..  I figure that date to be 12.25.2011, using the information above.  And the Mayans only believed that a "re-awaking of time and space" would occure on that date.  I don't believe it will be any major shift, and I wouldn't worry too much about it, as there is nothing we can do about it..   Just like 2000 when everybody was worried, nothing happened, except the people that were born on Feb 29, got treated to an extra birthday...
630243
beginning 35000-50000 year\nprofessional 60000-100000 year
432119
It takes about 365.2422 days to orbit the sun (i.e. a solar year). If we have a year be 366 days every four years, that averages out to 365.25 daysper year. This is still a bit large, so we declare 3 of the four century marks to *not* be leap years. That then gives an average of 365.2425, which is close enough for most purposes.\n\nSpecifics: Every year that is divisible by 4 is a leap year *except* those ending in 00. These are leap years only if divisible by 400.
102809
The Gregorian calendar, the current standard calendar in most of the world, adds a 29th day to February in all years evenly divisible by 4, except for century years (those ending in -00), which receive the extra day only if they are evenly divisible by 400. Thus 1996 was a leap year whereas 1999 was not, and 1600, 2000 and 2400 are leap years but 1700, 1800, 1900 and 2100 are not.
424465
Actually there are 364 + 1/4 days in a year. This has to do with the time that our Earth takes to complete one erbit around Sun. Now we have an arbiterary time period called week which has 7 days. So we have a normal year of 7 x 52 = 364 days. This leaves us with one 1/4 day per year left unaccounted. To make up for it, we have a leap year (365 days, 29 days in February) every four years.
418792
In 1564, France.\nApril 1st use to be the first day of the year according to the old calendar system. Since the change they wanted to remember the day and make it a joke day.
937504
24 x 365 or 366 if its a leap year
77427
365 and a quarter (hence the leap year every four years)