How many versions of the Gregorian calendar are there?

There are three versions of the yellow calendar, namely, the folk yellow calendar, the official yellow calendar and the lunar calendar.

1. Popular Gregorian calendar: Popular Gregorian calendar is the most common version of the Gregorian calendar, which is usually published by folk media or publishing houses, and its contents include information on branches, solar terms, festivals, good or bad luck, taboos and so on. It is one of the calendar tools commonly used by the people.

2. Official almanac: Official almanac is a kind of almanac formulated by the Chinese Astronomical Society. Its content is more accurate and scientific than the popular Gregorian calendar, mainly including knowledge of astronomy and meteorology. Official yearbooks are usually published by the Chinese Astronomical Society.

3. Lunar yellow calendar: The lunar yellow calendar is a kind of yellow calendar compiled according to the traditional Chinese lunar calendar, including heavenly stems and earthly branches, solar terms, festivals, good or bad luck, taboos and other information, similar to the popular yellow calendar now. Lunar calendar is usually published by folk media or publishing houses.