This is an algebraic number that has many interesting properties and was discovered in antiquity, not as a "unit" but as a ratio or proportion.This proportion is found in some geometrical figures as in nature in elements such as shells, ribs of the leaves of some trees, the thickness of the branches, etc. ((Ref: Wikipedia )). It is usually represented as the Greek letter φ (fi) and its mathematical formula would be the following …
in NetTuts studying the proportions of the contents of Each part of a theme can draw conclusions on how to apply the golden ratio to your template.
Some examples would be these:
1. Let's say that the width of your content is 900 pixels, if you divide it between the golden ratio (1.62) will give you the ratio that the post zone and the sidebar should have: 555 and 345 pixels respectively