Who commemorates the unified calendar of the world?

The unified calendar of the world was originally to commemorate the birth of Jesus, and this commemorative activity is called "Christmas".

In western countries, although the styles and ways of celebrating calendars may be different, the basic calendar framework is similar. A year is divided into 12 months, with different days in each month. A year begins in A.D. or the year of the Lord. The starting point of this calendar is 1 year, which is generally considered to be the year when Jesus was born.

However, there is some controversy about the exact year when Jesus was born. Although some historians believe that Jesus was born around 1 year, there is some evidence that his birth year may have been earlier. For example, according to some records in the Bible, Jesus may have been born in the year when the Roman Empire was founded, that is, around 754 AD.

However, because the starting point of the year is 1 and there is no "0", some scholars put forward the view that 2 1 century should start from 200 1 instead of 2000.

It is worth noting that in addition to the western calendar system, other parts of the world also have their own calendars and calendars, such as the Islamic era, the Buddhist era, the Jewish era, the Greek era and the Japanese era.