Thus Red Square in Moscow, named long before the Russian Revolution, meant simply "Beautiful Square".
Inside cave 13B at Pinnacle Point, an archeological site found on the coast of South Africa, paleoanthropologists in 2000 found evidence that, between 170,000 and 40,000 years ago, Late Stone Age people were scraping and grinding ochre, a clay colored red by iron oxide, probably with the intention of using it to color their bodies.
The term used for scarlet in the 4th century Latin Vulgate version of the Bible passage is coccumque bis tinctum, meaning "colored twice with coccus." Coccus, from the ancient Greek Kokkos, means a tiny grain and is the term that was used in ancient times for the Kermes vermilio insect used to make the Kermes dye.
Red color has a predominant light wavelength of roughly 620–740 nanometers.
Light with a longer wavelength than red but shorter than terahertz radiation and microwave is called infrared.
In addition, red is widely associated with socialism and communism, some examples being the flags of the Soviet Union The word can be further traced to the Proto-Germanic rauthaz and the Proto-Indo European root rewdʰ-. In the Akkadian language of Ancient Mesopotamia and in the modern Inuit language of Inuit, the word for red is the same word as "like blood".
In Portuguese the word for red is vermelho, which comes from Latin "vermiculus", meaning "little worm".
(See CMYK color model.) Traditionally, it was viewed as a primary subtractive colour, along with yellow and blue, in the RYB color space and traditional color wheel formerly used by painters and artists.
Reds can vary in shade from very light pink to very dark maroon or burgundy; and in hue from the bright orange-red scarlet or vermilion to the bluish-red crimson. In nature, the red color of blood comes from hemoglobin, the iron-containing protein found in the red blood cells of all vertebrates.In the United States, red pertains to the Republican Party and its supporters, as in Red states and blue states.Red is also a color widely used for getting attention, such as stop signs or royal dresses.The Egyptians used the root of the rubia, or madder plant, to make a dye, later known as alizarin, and also used it to color white power to use as a pigment, which became known as madder lake, alizarin or alizarin crimson.In Ancient China, artisans were making red and black painted pottery as early as the Yangshao Culture period (5000-3000 BC).Madder, a plant whose root could be made into a red dye, grew widely in Europe, Africa and Asia.