Is the old yellow calendar a lunar calendar or a solar calendar?

The lunar calendar is a traditional calendar in China, also known as the summer calendar, the Chinese calendar, the Korean calendar and the Chinese calendar. The lunar calendar is not a pure lunar calendar, but a combination of yin and yang. It takes the change period of the moon phase, that is, the length of the lunar month, plus the "24 solar terms" part of the trunk and branch calendar, and refers to the length of the solar tropical year. By setting leap months, the average calendar year will adapt to the tropic year. Therefore, the lunar calendar is a calendar based on the summer calendar and integrated with the solar calendar.