White

White is a color, the perception of which is evoked by light that stimulates all three types of color sensitive cone cells in the human eye in nearly equal amounts and with high brightness compared to the surroundings. A white visual stimulation will be void of hue and grayness.
White light can be generated in many ways. The sun is such a source, electric incandescence is another. Modern light sources are fluorescent lamps and light-emitting diodes. An object whose surface reflects back most of the light it receives and does not alter its color will appear white, unless it has very high specular reflection.
Since white is the extreme end of the visual spectrum (in terms of both hue and shade), and since white objects - such as clouds, snow and flowers - appear often in nature, it has frequent symbolism. Human culture has many references to white, often related to purity and cleanness, whilst the high contrast between white and black is often used to represent opposite extremes.

Etymology

The word white continues Old English hwīt, ultimately from a Common Germanic *χ^wītaz also reflected in OHG (h)wîz, ON hvítr, Goth. ƕeits. The root is ultimately from Proto-Indo-European language *k^wid-, surviving also in Sanskrit śveta "to be white or bright" and Slavonic světŭ "light".The Icelandic word for white, hvítur, is directly derived from the Old Norse form of the word hvítr. Common Germanic also had the word *blankaz ("white, bright, blinding"), borrowed into Late Latin as *blancus, which provided the source for Romance words for "white" (French blanc, Spanish blanco, Italian bianco, etc.). The root survives in English in the word black.

Color temperature

The best known way to generate white light is by the process called incandescence, or black body radiation where bodies of atoms with a certain temperature emit a certain type of radiation. For example, the color of a black body at a temperature of 2,848 kelvins. This is closely matched by incandescent light bulbs. The correlated color temperature of such a light bulb is 2,848 K. Daylight can vary from a cool red up to a bluish 5,600 K. Not all black body radiation can be considered white light: the background radiation of the universe, to name an extreme example, is only a few kelvins hot, and is not visible.
In astronomy the stellar class of stars are determined by the color temperature. For instance are white dwarfs small dense stars thought to be the final evolutionary state.
Computer displays often have a color temperature control, allowing the user to select the color temperature (usually from a small set of fixed values) of the light emitted when the computer produces the electrical signal corresponding to white. The RGB coordinates of white are (1.0, 1.0, 1.0). When light hits another object it bends.

Objects

Foam of a transparent and reflecting liquid, turning white when the size of the bubbles decreases.

Newly commissioned officers all in white, celebrate their new positions by throwing their midshipmen covers into the air as part of the U.S. Naval Academy class of 2005 graduation and commissioning ceremony.

White light reflected off objects can be seen when no part of the light spectrum is reflected significantly more than any other and the reflecting material has a degree of diffusion. People see this when transparent fibers, particles, or droplets are in a transparent matrix of a substantially different refractive index. Examples include classic "white" substances such as sugar, foam, pure sand or snow, cotton, clouds, and milk. Crystal boundaries and imperfections can also make otherwise transparent materials white, as in the milky quartz or the microcrystalline structure of a seashell. This is also true for artificial paints and pigments, where white results when finely divided transparent material of a high refractive index is suspended in a contrasting binder. Typically paints contain calcium carbonate or synthetic rutile with no other pigments if a white color is desired.

In nature

Snow and ice are normally white due to the diffusing structure of transparent water ice crystals. The same is true for many types of clouds where droplets of water diffuse the white light from the Sun. Many mountains with winter or year-round snow cover are named accordingly: Mauna Kea means white mountain in Hawaiian, Mont Blanc means white mountain in French. Changbai Mountains literally meaning 'Perpetually White' Mountains, marks the border between China and Korea and Mount Kilimanjaro's name could originate from Swahili meaning little white hill. The White Sea, an inlet of the Barents Sea on the northwest coast of Russia is undoubtedly named so due to the icy environment.
Beaches with sand containing high amounts of quartz also appear white, which may explain the number of islands called White Island around the world.

Symbolic dualism with black

Further information: black and white dualism

Black and white dualism in office spaces

White and black has the biggest visual contrast, this can easily be associated to other opposite concepts such as day and night or good and evil. White often represents purity or innocence in Western Civilization,particularly as white clothing or objects are easy to stain. In most Western countries white is the color worn by brides at weddings. Angels are typically depicted as clothed in white robes. Healing or "good" magic is called White magic. In early film Westerns the stereotypically "good guy" wore a white hat (earning them the name "White Hats") while the "bad guy" wore black (earning them the name "Black Hats"). This has given rise to the use of the names black hat and white hat for people who abuse and counter abuse of computer systems respectively. In popular culture this idea is sometimes reversed to play on reversal of stereotypes.
In taoism which has great influence in Eastern culture Yin and yang is usually depicted in black and white, depicting the two colors as opposites. The two opponents in board games of abstract strategy often has one as white, such as go, chess, and checkers.

Clothing

White clothing can be practically used as camouflage in snowy environments, or for reflecting harsh sunlight. However, most uniforms with white elements are used as a sign of authority - dissociating the wearer from manual labor or a dirty environment. In a highly formal social function, the traditional dress for men attending is white tie, or white tie and tails, a white bow tie and a swallowtail coat. Physicians and scientists are known for wearing white coats both as a practical measure as protecting from and showing spills and stains, and as a sort of uniform showing authority.
Many traditional sports use white uniforms for players, such as Wimbledon tennis, cricket, and baseball and basketball, where white is the color typically used for uniforms worn by the home team. This may be a result of the sports being played outside exposing players to direct sunlight for prolonged periods of time.