Phi (or the golden ratio, as it is sometimes known) has the value of approximately 1.618 and is usually denoted by the Greek letter φ. It is named after Phidias, the lead sculptor of the Parthenon in Greece, who is said to have employed it. This ratio plays a prominent role in architectural and furniture composition and design, where it is used to proportion objects for greater aesthetic appeal. Figure 1 illustrates its basic principle.
Figure 1: The golden ratio. The long portion of a straight line is 1.618 times longer than the short, and that the whole line is 1.618 times longer than the long portion
Phi has countless design applications. In woodworking, for example, tabletops are usually about 1.6 times longer than they are wide. Dining chairs often have backrests that are about 1.6 times taller than the seat height. The most appealing drawer proportions, and their placement, are also typically related to Phi.
A rectangle, such as a frame, door or window, that is 1.618 times taller than its width is called a golden rectangle. And a golden triangle, also know as the sublime triangle, is an isosceles triangle in which the two longer sides have equal lengths and in which the ratio of this length to that of the third, smaller side is the golden ratio:
MATH IS THE FUCKING RUDEST.
i love phi