Black

Black is a color with several subtle differences in meaning.

Color or light
Black can be defined as the visual impression experienced in directions from which no visible light reaches the eye. (This makes a contrast with whiteness, the impression of any combination of colors of light that equally stimulates all three types of color-sensitive visual receptors.)

Pigments that absorb light rather than reflect it back to the eye "look black". A black pigment can, however, result from a combination of several pigments that collectively absorb all colors. If appropriate proportions of three primary pigments are mixed, the result reflects so little light as to be called "black".

This provides two superficially opposite but actually complementary descriptions of black. Black is the lack of all colors of light, or an exhaustive combination of multiple colors of pigment.

Human
The term black is often used in the West to denote race for persons whose skin color ranges from light to dark shades of brown. For a discussion of usage, see the main entry at Blacks.

Usage, symbolism, colloquial expressions

In the Western world, black is most often used with a negative connotation. The reasons for this are various, but the most widely accepted explanations are that night is experienced by humans as negative and dangerous. A secondary reason is that stains are most visible as dark additions to pale materials. In traditional class-based cultures "pale" skin indicated genteel domestic or intellectual indoor-work as opposed to rough outdoor labor in the fields. Aspects of this black/white opposition are not unique to the West, as, for example in the Indian varna system. African and African-American writers such as Franz Fanon, Langston Hughes, Maya Angelou, and Ralph Ellison in particular identify a number of negative symbolisms surrounding the word "black", arguing that the good vs. bad dualism associated with white and black provide prejudiced connotations to color metaphors for race.

1. A "black day", in these cultures, would refer to a sad or tragic day. The Romans already marked fasti days with white stones and nefasti days with black.

e.g. the Black September in Jordan refers to a month in which thousands were killed.
Black Monday, stock crash of October 19, 1987
Black Tuesday is the day of the stock market crash in 1929 which is the start of the Great Depression.
Black Wednesday caused Britain to pull out of the ERM(European Exchange Rate Mechanism ).
Black Thursday, date preceding the stock crash of October 29, 1929, forecasting the stock market crash and the Great Depression
Black Friday, various tragic events.

2. many poems and songs use the word black negatively (e.g. Paint it black (Rolling Stones), Baby's in black (Beatles), Black eyed dog (Nick Drake).
3. In these cultures, the color black is often used in painting, film, and literature to evoke a sense of the fear or to symbolize death. It has also been adopted a symbolic color of the Halloween festival.
4. In English heraldry, black means darkness, doubt, ignorance, and uncertainty. (The American Girls Handy Book, p. 370)
5. Black is often a color of mourning. Historically, widows and widowers were expected to wear black for a year after the death of their spouses.
6. Black comedy is a form of comedy dealing with morbid and serious topics.
7. Black magic is an evil form of magic, often connected with death.
8. In computer security, blackhat is an attacker with evil intentions.
9. A blacklist is a list of undesirable persons or entities.
10. Evil witches are sterotypically dressed in black and good fairies in white. Melodrama villains are dressed in black and heroines in white dresses. In many Hollywood Westerns, bad cowboys wear black hats while the good ones wear white. Funeral dress is black, wedding gowns are white.
11. The black-market is illegal.
12. Blackmail is illegal and is perceived as immoral.
13. The black sheep of the family is the ne'er-do-well.
14. The infamous "black hole of Calcutta."
15. To black-list someone is to put them on a "bad" list.
16. To blackball them is to block them from being admitted.
17. Black thoughts are dark ones.
18. A black mood is a bad one (e.g. Winston Churchill's depression, which he called "my black dog").
19. A black cat usually means bad luck.
20. If you sink the black eight-ball in billiards, you lose. (The ball with which you sink all others is the white cue ball.)
21. A black mark against you is a bad thing.
22. A dark night is "black as hell".
23. A black-hearted person is mean and unloving.
24. Black propaganda is the use of known falsehoods, partial truths, or masquerades in propaganda to confuse an opponent.

However, black can have positive symbolism.

1. In the Maasai tribes of Kenya and Tanzania, the color black is associated with rain clouds, becoming a symbol of life and prosperity.
2. In Western fashion, black is considered reliably stylish.

The colloquialism "the new black" is a reference to the latest trend or fad, on the basis that black is always fashionable.

3. Black is seen as a color of seriousness and authority.

Many priests of the older religious denominations traditionally wear black.
The beltzak ("blacks" after their uniform) are the riot control units of the Basque Autonomous Police

4.To say one's accounts are "in the black" is used to mean that one is free of debt.

(Being "in the red" is to be in debt—in traditional bookkeeping, negative amounts, such as costs, were printed in red ink, and positive amounts, like revenues, were printed in black ink, so that if "the bottom line" is printed in black, the firm is profiting.)

5. The most sought-after rank in any martial art is a black belt.

Black can also be used in many non-judgmental ways.

1. In arguments, things can be black-and-white, meaning that the issue at hand is dichotomized. However, this dualism is fraught with danger, as one may assign the colors "black and white" to bad and good, respectively.

2. Black frequently symbolizes ambiguity, secrecy, and the unknown.

A black project is a secretive project, like Enigma Decryption, Narcotics, or police sting operations.
The blackshirts were Italian Fascist militias (negative for anti-fascists, but presumably positive for the original fascists themselves)
Some organizations are called "black" when they keep a low profile, like Sociétés Anonymes and secret societies.

3. Black is often used in Western culture to refer to race. For more details, see Blacks and Color metaphors for race.
4. The term "black hole" is applied to collapsed stars. This term is metaphorical in the extreme, because few properties of black objects or black voids apply to black holes. However, light emitted within a black hole's event horizon cannot escape, hence a black hole cannot be directly observed.
5.The national rugby team of New Zealand is called the All Blacks, in reference to their black outfits.
6. Association football (soccer) referees traditionally wear all-black uniforms, however nowadays other uniform colors may also be worn.
7. In auto racing, a black flag signals a certain driver to go into the pits.
8. Black is also used for anarchist symbolism, sometimes splitted in diagonal with other colors for further symbolism. It is also sometimes an anarchist dress code, with a practical benefit of not attracting attention and making later identification of a subject difficult. This strategy referred to as a black block.
9. In German politics 'black' is used colloquially to refer to the conservative parties CDU and CSU
10. In ancient China, black was the symbol of North and Water, one of the main five colors. There is no negative or positive meaning associated with it.
11. Black is the color of the snooker ball which has a 7-point value, and also the eighth billiard ball. In the game of eight ball, this ball is the ultimate object of the game, but, if accidentally sunk, means instant loss of the game.
12. A polished black mirror is used for scrying, and is thought to help see into the paranormal world without interference or distraction.
13. The modern subculture of Goths dress predominantly in black.