What year is year B?
Year B is one of the first months of the lunar calendar, such as 1905, 1965 and 2025(60-year cycle), that is, literally, trunks and branches are equivalent to branches and leaves of the lunar calendar. In ancient China, the sky was dominant and the earth was subordinate. The connection between the sky and the trunk is called heavenly stems, and the connection between the ground and branches is called earthly branches. Together, it is called heavenly stems and earthly branches, or "dry branch" for short.
Introduction to Tiangan:
There are ten heavenly stems, namely, A, B, C, D, E, Ji, G, Xin, Man and Ghost, and twelve earthly branches, namely, Zi, Ugly, Yin, Mao, Chen, Si, Wu, Wei, Shen, You, Xu and Hai.
The ancients put them together in the order of Jiazi, Ugly B and Bingyin (that is, the sky turns six times and the earth turns five times, which is just a cycle). There are 60 pairs from Jiazi to Guihai, which are called Jiazi.
The ancients in China used these 60 pairs of branches to represent the serial numbers of years, months, days and hours, and this is the chronology of branches.