De Divina Proportione - 'The Golden Ratio'.
a to b = 1:1.618
a+b to a = 1:1.618
A harmonious mathematical proportion that is supposed to provide a 'pleasing visual effect'.
Specifications:
The golden section of 100cm / 1.618 = 61.80cm
100cm / 1.618cm = 61.80cm
100cm = 61.80 + 38.20
the ratio of 61.80cm to 38.20cm is 1:1.618
Within application:
As you can see from the very simple example, the effectiveness of the golden ratio is somewhat successful in providing a nice bit of white space for the text breathe on the page. However, the use of any grid which uses units and increments of 'x' will render a successful layout, it's the use of common sense and logic that creates a successful layout.
Van De Graaf Canon
Van De Graaf was formed on the basis that ancient texts had a tendency to follow the same rule in terms of border size and text block size.
It is a good way of establishing a grid using unusual diagonal lines to which intersect and where they collide, the text box/margins are made.