The document discusses the Golden Mean (also called the Golden Ratio or Golden Section), which is a ratio of approximately 1.618 that is found throughout nature and considered aesthetically pleasing. It relates to the Fibonacci sequence and can be used to create Golden Rectangles and spirals. Many artists have incorporated the Golden Mean into their works, such as Leonardo Da Vinci in the Mona Lisa. Examples of the Golden Mean can also be found in architecture, music, and nature.