This document discusses the science behind various design elements including color, typography, alignment, layout, proximity, white space, and images. It provides information on how colors like red, orange, green, blue, and purple can create different emotions. It also discusses typefaces like Helvetica, Baskerville Old Face, and Brush Script and how pairing fonts impacts design. Layout principles from the golden ratio, rule of thirds, and heat maps tracking eye movement are covered. Proximity, white space, and when to use people versus action images are also summarized.