**1. The golden ratio**

THE golden ratio is believed to have aesthetically pleasing properties. The golden ratio is a naturally occurring number that has been the subject of interest since ancient Greek times, and has been used in architecture, art, books and music since at least the time of the Renaissance. For example, artists have used the golden rectangle to select the most aesthetically appealing canvas dimensions.

If the golden rectangle is aesthetically pleasing, then it makes sense to use the golden rectangle when preparing images to be inserted in presentations, proposals, reports, blog posts, etc. The image above has the dimensions of a golden rectangle and, more interestingly, the shape of the spiral above the street lamp is a golden spiral.

Denoted by the Greek letter phi, Φ, the golden ratio is an irrational number equal to:

**2. The golden rectangle**

The golden rectangle is the name given to any rectangle for which the ratio of the longer side ‘a’ to the shorter side ‘b’ is the golden ratio.

Interestingly, if the two sides of a rectangle are in the golden ratio then the ratio between the sum of the two sides and the larger side is the same as the ratio between the larger side and the smaller side.