The old yellow calendar is an almanac that can display multiple sets of calendars such as the Gregorian calendar, the lunar calendar and the Ganzhi calendar at the same time, and attach a large number of rules and contents related to seeking good luck and avoiding evil. The main contents of the old yellow calendar include: the twenty-four solar terms, good and bad luck, bad luck, evil spirits, harm, Nayin, stems and branches, twelve gods, duty, fetal gods, constellations, moon phases, auspicious gods and evil spirits, Peng Zu Baiji, six Yao, nine stars, fleeting years, Tai Sui, Sanyuan Jiuyun, Xuankong Jiuxing, week, zodiac, orientation, choosing auspiciousness, dressing and so on.