There are 365 days a year that are right or wrong.

A year is defined as the time required for the earth to make one revolution around the sun, which is about 365.25 days. This is based on the observation and study of the movements of the sun, the earth and the moon.

For convenience, we usually define a year as 365 days instead of 365.25 days. This is mainly because the number 365 is easy to calculate, but it will lead to a slight deviation between our calendar and the actual solar calendar. This is why we need to add an extra leap year every four years to keep the calendar in sync with the solar calendar.

In the leap year system, every hundred years are divided into three periods: non-leap year (average year), each period is 365 days; Leap year (whole hundred years), each period is 366 days; The last year of leap year (century year) has 366 days each. This system ensures that our calendar is basically the same as the solar calendar.

There is a more accurate calendar in a year-Gregorian calendar, which accurately calculates about 365.25 days per year, and inserts an extra leap year every four years to correct the deviation.

The difference between twelve months in a year:

1, January: It's the beginning of a year and the cold winter. People usually celebrate the New Year this month.

February: The weather is usually very cold, and sometimes it snows. This is the month of Valentine's Day.

March: The weather gets warmer, which is the month when spring comes, and sometimes flowers begin to bloom.

April: The weather is usually warmer, and sometimes there will be spring rain, which is the month when everything recovers.

May: It's getting hotter and hotter, and it's another month of alternating spring and summer. People usually celebrate Mother's Day this month.

June: It's usually hot, which is the beginning of summer. Students usually end their term this month.

July: It is usually one of the hottest months of the year. People usually spend their holidays and travel this month.

August: It is usually one of the hottest months in summer, and people usually continue their holidays and travel in this month.

September: The weather begins to turn cold, which is a month of alternating summer and autumn. Students usually return to school this month.

10, October: The weather is usually cooler, which is the beginning of autumn. People usually celebrate Halloween this month.

1 1, 1 1 month (1 1 month): the weather is getting colder, and it is a month of alternating autumn and winter. People usually prepare for Christmas this month.

12,1February: It is the last month of winter, and the weather is usually very cold. People usually celebrate the New Year this month.