Red focuses behind the retina which forces the lens grows more convex to pull it forward. Therefore, we perceive that red areas are moving forward. This may explain why red captures attention.

Yellow-based reds are “tomato” reds. Blue-based reds are “berry reds.” Some say that males are more attracted to the tomato reds: females to the berry reds.

Context is everything when using red. For example, when red is place on a black background, it glows with an otherworldly fire; on a white background, red appears somewhat duller; in contrast with orange, red appears lifeless. Notice that the red square appears larger on black.

Regardless of how it is used in a design, a little bit of red goes a long way.

In Russia, the word for "red" means beautiful.

Red is the color of good luck in Asia and is the most popular color in China.

Most Japanese children draw the sun as a big red circle.

In East Asian stock markets, red is used to denote a rise in stock prices. (Note: In North American stock markets, red is used to denote a drop in stock prices.)

Red is an auspicious color for marriage. Brides in India and Nepal wear red saris; in Japan, a red kimono symbolizes happiness and good luck.

Thanks to its long wavelength, red is one of the most visible colors in the color spectrum (second only to yellow).

Its ability to instantly grab people's attention is the reason why it's often used to warn people of impending danger. Think: stop signs, sirens, fire engines, and red traffic lights.

Red is also used to convey danger in a non-literal way. Some examples include using the phrase "in the red" to describe financial loss or "red flag" to indicate when something is wrong with a person or situation.

People tend to associate red with negative, danger-bearing emotions. This could be because it is the color of fire, blood, and sometimes of poisonous or dangerous animals.

Across cultures, people intuitively associate red with the concept of anger. This relationship makes sense given that many people get red in the face from increased blood flow when they're angry.

The expression "seeing red" is thought to be based on the physical characteristics associated with anger, including redness of the face and neck, which are caused by elevated blood pressure.

It's not just mood and emotions that the color red can affect. In the arena of sports, wearing the color red can also increase your chances of winning.

In the 2004 Olympics in Athens, competitors in four sports—boxing, Greco-Roman wrestling, freestyle wrestling, and taekwondo—were randomly assigned red or blue clothing. In all four competitions, red-clad contestants won more fights.

Many think these results are due to the link between red and perceived dominance. For instance, donning a red uniform may cause an athlete to feel dominant and perform more aggressively. Alternatively, athletes in red may be seen as more aggressive, more dominant, and more likely to win a physical competition not only by their opponents but also by the referees.⁷

Whatever the reason, it is clear that red-clad athletes tend to have a significant advantage over their opponents. (Maybe this is why so many athletes, including the great Tiger Woods, wear red clothing when they compete.)

But red does not always signal danger and aggression. Perhaps not surprisingly, red is also linked to passion, love, and desire. These associations could explain why people wearing red are consistently rated as more attractive.

In a landmark study published in 2008, researchers showed men an image of a woman and asked them to rate her attractiveness. Some men saw a woman wearing a red shirt while others saw the same woman wearing a blue shirt. Results showed that men rated the woman in red as more desirable than the same woman in blue.

In healing, use red to bring warmth and burn out disease.

Colors were so powerful in traditional cultures that red objects were believed to convey health through their color alone.

For example, most red stones such as garnets and rubies were believed to have health-giving and disease-preventing properties. In Rome, children wore red coral as a talisman to protect them from diseases, and in China, for similar reasons, children always wore a piece of red clothing.

Red can also represent power, a relationship that can be found all over modern-day society. The "power tie" worn by businessmen across the globe is, traditionally, red. And don't forget the hallowed "red carpet" that is only rolled out for the most prestigious celebrities and dignitaries.

According to some, this association with power and wealth is the reason why women find men dressed in red so attractive.

In the aura red signifies materialism, materialistic ambition, a focus on pleasures and a quick temper.

In color psychology, red provokes the strongest emotions of any color. While cool colors like green and blue are generally considered peaceful and calming, red is considered the warmest and most contradictory of the colors. In fact, this fiery hue has more opposing emotional associations than any other color: Red is linked to passion and love as well as power and anger.