Two alternative arrangements of the sixty-four hexagrams of the I Ching, the Book of Changes. Each line is either broken, representing Yin, or unbroken, representing Yang, though each figure is generally seen as being composed of two trigrams.

The cycle of the hexagrams does not follow a single inevitable sequence in quite the same way as the Phases of the Moon, and complete Yin and complete Yang are generally classified as the first two hexagrams in any treatment.