The I Ching or "Yì Jīng", also known as the Classic of Changes, Book of Changes and Zhouyi, is one of the oldest of the Chinese classic texts. The book contains a divination system comparable to Western geomancy or the West African Ifá system; in Western cultures and modern East Asia, it is still widely used for this purpose.
You should not ask the Book a few times on the same question. Only the first answer would be truthful.