Is the solar calendar a national calendar or a lunar calendar?

The "solar calendar", also known as the "solar calendar", is based on the earth's revolution around the sun for one year, which is common in all countries, so it is also called the "western calendar". Our country began to adopt the solar calendar in the first year of the Republic of China, so it is also called the "national calendar". In order to be symmetrical with China's old calendar, it is also called the "new calendar". The lunar calendar, also known as the lunar calendar, takes the moon's orbit around the earth as a month and the earth's orbit around the sun as a year, which is actually equal to the lunar calendar. China adopted this calendar before the Republic of China, which is symmetrical with the current calendar, hence the name "Old Calendar". Most people think that the lunar calendar is suitable for farmers, so it is called "lunar calendar". Because the current lunar calendar is the solar calendar built in the first month of the Xia Dynasty, it is also called the "summer calendar".