Knowledge of the Golden Section, ratio, or proportion has been known for a very long time. The Egyptians knew about it and the Greeks learned about it from them. It is called phi, Φ, in honor of Phideas, the architect of the Parthenon, and is approximated by the irrational fraction 0.618034. Shamans, priests, and artists throughout the world and across history have understood and applied Φ to ritual, architecture, art and the crafting of musical instruments and everyday objects.
Recall Vitruvian Man, a drawing by Leonardo showing man within the circle and the Golden Ratios in the human body. Le Corbusier's The Modular represents a more recent study of the Golden Ratio in the human form. For example, the finger bones are in approximate Φ ratio to each other, and the position of features on the human face is related to Φ.
The golden ratio is an irrational mathematical constant, approximately 1.618, and it is denoted by the Greek letters ф (phi), or sometimes τ (tau). The Ancient Greeks applied the ratio into their art, music, and architecture.