The golden ratio should not need any introduction to those who have studied math and design in school. Some designers apply these mathematical concepts to come up with more visually appealing works. This infographic from companyfolders.com covers a few golden ratio facts:
The Golden Ratio: a designer's guide. The Golden Ratio is a beautifully simple piece of mathematical theory that can help make your designs feel well proportioned and pleasing on the eye. We explain how to use it.