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Red barns -

Red barns are traditionally found across North America, but why are they painted red? Farmers started to use a coat of paint made from locally sourced ingredients in order to help preserve the wood. 

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Red barns -

They used a mixture of linseed oil, lime, milk, and iron oxide. The iron oxide, which was extracted from soil, gave barns their distinctive red hue. 

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Traffic lights -

Red has the longest wavelength of any color, making it visible at a longer distance, hence its use as a "stop" sign in traffic lights. The wavelengths decrease in yellow and green, respectively, making them less visible from afar when compared to red. 

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Yellow tennis balls -

You're probably familiar with fluorescent yellow tennis balls, but did you know that up until the 1970s, tennis balls used to be black or white?

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Yellow tennis balls -

So, why the yellow balls? Well, because the color made it easier to follow on color television. The new tennis ball color was adopted in 1972.

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Pink bubble gum -

Bubble gum is traditionally pink for one simple reason. Its inventor, Walter Diemer, only had access to pink food coloring dye at the factory where he first produced bubble gum. 

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Yellow pencils -

Pencils date back to the late 1800s. This was when pencil maker Franz von Hardtmuth of Austria thought about giving them a royal look. And how would he do that? By making them yellow. 

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Yellow pencils -

He associated yellow with royalty due to the colors of the Austro-Hungarian flag. Yellow was also used by Chinese royalty, the country where the best graphite was sourced from. 

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Red carpets - Celebrities walk down the red carpet because important people have done so for centuries. In the 458 BCE play 'Agamemnon' by the Greek playwright Aeschylus, there is a reference to King Agamemnon arriving home to a red carpet.

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Red carpet -

Here is a painting depicting a red carpet event, entitled 'The Procession of the Order of the Bath,' at Westminster Abbey, London, 1749.  

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White flag -

A white flag is a universal sign of surrender. Its use is easily explained: white cloth was the most widely available fabric throughout history. Plus, it was easier to spot on the battlefield.

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Doctors' white coats -

Back in the 1800s, doctors wouldn't have been seen wearing white coats. In fact, they'd usually wear black.   

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Doctors' white coats -

But as medical knowledge advanced and an effort to keep things germ-free was made, white coats were introduced. 

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Blue first-place ribbons -

Blue ribbons have come to symbolize first place in a number of different settings. Its history dates back to the Cross of the Holy Spirit medal awarded to knights by King Henry III of France.

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Blue first-place ribbons -

Pictured is a painting detail of the Knights of the Cross of the Order of the Holy Spirit, created in 1578 and abolished in 1791.

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Pink for baby girls and blue for baby boys -

Pink clothes for girls and blue clothes for boys was a concept introduced by department stores in the early 1900s.

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Pink for baby girls and blue for baby boys -

Up until then, all babies would wear white, and they would all wear dresses too. 

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Yellow taxis -

Yellow cabs are popular across the US, especially in cities like New York and Chicago, but why yellow? Well, John Hertz (founder of the Hertz rental car company) actually commissioned research to find the most visible color for a car. It was yellow.

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Pink doughnut boxes -

Pink doughnut boxes started to be used in Los Angeles in the '80s because they were cheaper than white ones.  

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Black and white crosswalks -

The British government started to experiment with crosswalks in the late 1940s, but the first versions using metal studs were inefficient. The first official black and white zebra crossing (as it's called in the UK) was installed in 1951 in Slough, England.

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Blue denim -

Denim has been a staple in our wardrobes for a very long time, but why is it blue? The answer is simple: the indigo used to dye the denim binds to the cloth's threads. The excess is then washed away and we're left with the classic blue we all know and love. 

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Green dollar bills -

Before dollar bills became green, counterfeits were a big problem. This is because before the Civil War, bills were printed by different entities, and had different sizes and colors. The new green and black bills were difficult to counterfeit.   

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Red fire engines -

There are a few theories as to why fire trucks are red. The most popular one is that red was the cheapest paint available, and as such, it was used by fire departments, which were operated by volunteers. 

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Yellow school buses -

In the US, school buses are yellow with black lettering and a white roof. But why? The color was selected at a 1939 conference for being the most visible. Black lettering provides the greatest contrast, and the top is white to reflect sunlight, making it even brighter, and therefore more visible.

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Black and white soccer balls -

For many years, soccer balls were brown because they were made of natural leather. In 1970, FIFA introduced the black-and-white 'Telstar' in the Mexico World Cup. The color made it easier for viewers to see it on TV. 

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White toilet paper -

The vast majority of toilet paper is bleached, hence the white color. The process also removes lignin, which makes the paper softer. The final reason why toilet paper is white is because the color is associated with cleanliness. 

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White civilian airplanes -

Most civilian airplanes are white for a number of reasons. One is that painting airplanes is very expensive. Another reason is that white reflects sunlight and doesn't absorb heat. Any anomalies (e.g. cracks) are easier to spot, and white is also seen better by birds, avoiding collisions. 

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Black tires -

Tires used to be white, as this is the natural color of rubber. These, however, wore out quickly. So, in 1917 manufacturers started to add carbon black to tires. This was a game-changer for both durability and performance. It also made tires black, as we now know them.  

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Red striped candy canes -

Up until the 1800s, candy sticks used to be white. Story has it that the red was used to symbolize Christ's blood, but the decision to add the color was probably based on marketing alone. At the time, the design was pretty popular.  

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Red fire hydrants -

Fire hydrants used to be red to make them visible to pedestrians. This is no longer the case, and other colors are used to indicate things such as water source and power.

Sources: (Ranker) (Listverse)

See also: Fascinating color meanings around the world

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