Because it was widely available, yellow ochre pigment was one of the first colors used in art; the Lascaux cave in France has a painting of a yellow horse 17,000 years old. Ochre and orpiment pigments were used to represent gold and skin color in Egyptian tombs, then in the murals in Roman villas. In the early Christian church, yellow was the color associated with the Pope and the golden keys of the Kingdom, but was also associated with Judas Iscariot and was used to mark heretics. In the 20th century, Jews in Nazi-occupied Europe were forced to wear a yellow star. In China, yellow was the color of the Middle Kingdom, and could be worn only by the Emperor and his household; special guests were welcomed on a yellow carpet.
According to surveys in Europe, Canada, and the United States, yellow is the color people most often associate with amusement, gentleness, humor, and spontaneity, but also with duplicity, envy, jealousy, avarice, and, in the U.S., with cowardice. In Iran it has connotations of pallor/sickness, but also wisdom and connection. In China and many Asian countries, it is seen as the color of happiness, glory, harmony and wisdom.
The word yellow comes from the Old English geolu, geolwe (oblique case), meaning "yellow, yellowish", derived from the Proto-Germanic word gelwaz "yellow". It has the same Indo-European base, gʰel-, as the words gold and yell; gʰel- means both bright and gleaming, and to cry out.
The English term is related to other Germanic words for yellow, namely Scots yella, East Frisian jeel, West Frisian giel, Dutch geel, German gelb, and Swedish and Norwegian gul. According to the Oxford English Dictionary, the oldest known use of this word in English is from The Epinal Glossary in 700.
Color printing typically uses ink of four colors: cyan, magenta, yellow, and key (black). When CMY "primaries" are combined at full strength, the resulting "secondary" mixtures are red, green, and blue