Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz. In physics, the term light sometimes refers to electromagnetic radiation of any wavelength, whether visible or not. Primary properties of light are intensity, propagation direction, frequency or wavelength spectrum, and polarisation, while its speed in a vacuum, 299,792,458 meters per second (about 300,000 kilometers per second), is one of the fundamental constants of nature. Light, which is emitted and absorbed in tiny "packets" called photons, exhibits properties of both waves and particles. This property is referred to as the wave–particle duality. The study of light, known as optics, is an important research area in modern physics. The speed of light in a vacuum is defined to be exactly 299,792,458 m/s (approximately 186,282 miles per second). The fixed value of the speed of light in SI units results from the fact that the metre is now defined in terms of the speed of light. Different physicists have attempted to

Luminosity is a measurement of brightness. In photometry, luminosity is sometimes incorrectly used to refer to luminance, which is the density of luminous intensity in a given direction. The SI unit for luminance is candela per square metre. The luminosity function a.k.a. luminous efficiency function describes the average visual sensitivity of the human eye to light of different wavelengths. There are two luminosity functions in common use. For everyday light levels, the photopic luminosity function best approximates the response of the human eye. For low light levels, the response of the human eye changes, and the scotopic curve applies. In Adobe Photoshop's imaging operations, luminosity is the term used incorrectly to refer to the luma component of a color image signal; that is, a weighted sum of the nonlinear red, green, and blue signals. It seems to be calculated with the Rec. 601 luma co-efficients (Rec. 601: Luma (Y’) = 0.299 R’ + 0.587 G’ + 0.114 B’). The "L" in HSL color space is sometimes said incorrectly to stand for luminosity. "L" in this case is calculated as 1/2 (MAX + MIN), where MAX and MIN refer to the highest and lowest of the R'G'B' components to be converted

Sunlight, in the broad sense, is the total frequency spectrum of electromagnetic radiation given off by the Sun. On Earth, sunlight is filtered through the Earth's atmosphere, and solar radiation is obvious as daylight when the Sun is above the horizon. When the direct solar radiation is not blocked by clouds, it is experienced as sunshine, a combination of bright light and radiant heat. When it is blocked by the clouds or reflects off of other objects, it is experienced as diffused light. The World Meteorological Organization uses the term "sunshine duration" to mean the cumulative time during which an area receives direct irradiance from the Sun of at least 120 watts per square meter. Sunlight may be recorded using a sunshine recorder, pyranometer or pyrheliometer. Sunlight takes about 8.3 minutes to reach the Earth. Direct sunlight has a luminous efficacy of about 93 lumens per watt of radiant flux, which includes infrared, visible, and ultraviolet light. Bright sunlight provides illuminance of approximately 100,000 lux or lumens per square meter at the Earth's surface. Sunlight is a key factor in photosynthesis, a process vital for life on Earth. To calculate the amount of

"Light" is a song by industrial rock band KMFDM from their 1993 album Angst. The single was first released in 1994 and contains nine different remixes of the song. "Light" peaked at No. 31 on the Billboard Dance/Club Play Songs Chart in May 1994. The single was re-released as a 7" in 2009, and the song was remixed and released as "Light 2010" on December 17 2010.

Light (Japanese: ￣ﾁﾲ￣ﾁﾋ￣ﾂﾊ - Hikari) is the tenth episode of season 1 of the Air TV series originally aired 2005-03-03. TV Air 10

Light is a 2003 album by American contemporary Christian music artist Jeff Deyo.

Light is a fictional character in the long-running British science fiction television series Doctor Who.

Light was an extremely powerful, almost God-like alien being. Long ago, he took a survey of all organic life in the universe, but almost as soon as he finished 'it all started changing.' Light went into hibernation in his spaceship, hidden in the basement of Gabriel Chase. Light began to campaign against evolution and change, deciding to destroy all life so that his catalogue would never be out of date again. Before he could carry out his plan, though, the Doctor told Light that even he was changing. Unable to cope with this fact, Light 'dissipated' in the main hallway of the house.

Light is a science fiction novel written by M. John Harrison and published in 2002. It received the James Tiptree, Jr. Award and a BSFA nomination in 2002, and was shortlisted for the Arthur C. Clarke Award in 2003. The book centres on the lives of three individuals — the physicist (and serial killer) Michael Kearney, on the verge of a breakthrough in theoretical physics sometime in 1999; Seria Mau Genlicher, the cybernetically-altered female pilot of a "K-ship", and the ex-space pilot and adventurer Ed Chianese. Seria Mau and Ed's stories take place in the year 2400 AD. The lives of these three individuals are linked in many ways, though most tangibly by the presence of a mysterious creature called The Shrander, who appears in many guises to all three characters throughout the novel (with anagrammatic names of Sandra Shen and Dr. Haends). They are also linked by the Kefahuchi Tract, a space-time anomaly described as "a singularity without an event horizon", an object of awe and wonder that has been the ruin of many civilisations attempting to decode its mysteries. The Shrander takes many forms, most often with the body of an old woman in a maroon wool coat, with a horse's skull

This article is about the car. For other uses, see Automotive lighting. The Light was an automobile built in Detroit, Michigan by the Light Motor Car Company in 1914. The Light was a conventional vehicle with a six-cylinder, 30 hp engine. It came as a touring model selling for $1,250.

Light is the third album by reggae singer Matisyahu, which was released on August 25, 2009. It was anticipated since his major label debut Youth released three years before. The album has been highly successful in the reggae world, holding the top spot on the billboard reggae albums chart for 34 weeks. Matisyahu had been working on his third album for nearly two years, making it the longest time he has ever spent making a record. The follow-up to Youth had been delayed several times before its release. First scheduled for early 2008, Light was pushed back numerous times because Matisyahu continued to tour off and on since the release of Youth. The new album's release date was set for April 21, 2009, but on March 3, the release date was pushed back to May 12, 2009. Then, once again, he pushed the release back, this time to Summer 2009, ostensibly because Matisyahu decided to record more new songs. That date had already passed, and in a message from Matisyahu on Twitter the album is due to release on August 25. On May 27, Matisyahu's FaceBook page stated that the album was going to come out on August 25. On June 23 Light was made available for preorder on iTunes, with the single "One

Light is an edition of a book written by M. John Harrison.

In theology, light or divine light is a term used to refer to an aspect of divine presence, specifically an unknown and mysterious ability of God, angels, or human beings to express themselves communicatively through spiritual means, rather than through physical capacities. In this context, "light" can carry the full range of divine or else human-understandable concepts ranging from pure emotion up to concepts and conceptualizations. Hence human beings are said to be recipients of knowledge, "truth," or "illumination," originating from God (in a transcendent reality) to human beings in the 'known universe,' through spiritual means. Various local religious concepts exist: Light is the core concept in Iranian mysticism. The main roots of this thought is in the Zoroastrian beliefs, which defines The supreme God Ahura Mazda as the source of light. This very essential attribute is manifested in various schools of thought in the Iranian Religions and philosophy. Latter this notion has been dispensed into the whole Middle East, having a great effect of shaping the paradigms of different religions and philosophies emerging one after another in the region. After the Arab invasion, this

"Light" is the fifth episode of the first season of the science fiction television show Stargate Universe. Following from the end of "Darkness", the Destiny is on a collision course with a star. A plan is devised to use the last working shuttle to evacuate to one of the three planets. However, there is only room for seventeen people and no time for additional trips, so a lottery is held to determine who will leave.

Light is a single by Music for Pleasure and was released in 1982. All songs written and composed by Mark Copson, Christopher Oldroyd, Ivor Roberts and David Whitaker.