Yellow signifies joy, happiness, betrayal, optimism, idealism, imagination, hope, sunshine, summer, gold, philosophy, dishonesty, cowardice, jealousy, covetousness, deceit, illness, hazard and friendship. Yellow warns of danger, and is used in signs to warn drivers of upcoming curves, pedestrian crossings, and animal crossings. When someone is seen to be afraid or "chicken" they are called "yellow," or “yellow-bellied” which is the same as calling them a coward. Notice, in the video, right after her "orgasm," the woman is both excited and "afraid" looking. The color yellow helps activate the memory, encourage communication, enhance vision, build confidence, and stimulates the nervous system.
The color yellow is a spontaneous and yet at the same time is considered an unstable color. It is often associated with food, and is highly used in children’s products and marketing advertisements aimed at children, as it stimulates emotion rather than logic. Perceived as a "childish" color by men (who have a strong tendency to logic as opposed to women who are easily moved by emotion,) yellow should not be used when marketing products to educated, prestigious, nor to wealthy men. If yellow is overused, it can have a disturbing effect. It is a proven fact that babies cry more in rooms painted yellow. Too much yellow overstimulates peoples reasoning, and causes loss of focus and makes it hard to complete a task. The shade of yellow determines its effect: Yellow-green can mean deceit, and creates a feeling of disorientation. Orange-yellow imparts a sense of establishment. Clean light yellow clears the mind, making it active and alert making one "excited". Cheerful sunny yellow is an attention getter. Too much yellow causes people to have a tendency to lose their tempers, which has been demonstrated in experiments using yellow rooms. Additionally, babies will cry more often is a room painted yellow. It is the most difficult color for the eye to take in, so it can be overpowering if overused and causes people to become excited. However, at the same time yellow enhances concentration, hence its use for legal pads.
Yellow signs warn drivers of upcoming curves, pedestrian crossings, and animal crossings. In most cultures, it also represents sunshine, happiness, and warmth. In religions, such as Hinduism and ancient Egyptian, it is often associated with their deities. Although not often found in national flags, yellow is prominently used both in the flag of Vatican City (the world's smallest state) and the Holy See -- which is the jurisdiction ruled by the "pope, " currently "pope" Francis I.
In the 1890s pencil makers in the United States began coloring their writing implements yellow due to yellows association with Chinese royalty, and China at that time had the best graphite. Today, American pencils retain this color.
Yellow is the most visible color of the spectrum, its high reflectance (Reflectance: A measure of the ability of a surface to reflect light or other electromagnetic radiation, equal to the ratio of the reflected flux to the incident flux.) of light allows it to act as if a secondary light source. It is the first wavelength of light processed by the human eye (which is why its use in certain signage and on some emergency rescue vehicles). Our peripheral vision (the ability to see side or fringe areas when we look straight ahead) is 2 1/2 times higher for yellow than for red.