The form, design and implementation of CPUs have changed over the course of their history, but their fundamental operation remains almost unchanged. Principal components of a CPU include the arithmetic logic unit (ALU) that performs arithmetic and logic operations, processor registers that supply operands to the ALU and store the results of ALU operations, and a control unit that orchestrates the fetching (from memory) and execution of instructions by directing the coordinated operations of the ALU, registers and other components. Most modern CPUs are microprocessors, meaning they are contained on a single integrated circuit (IC) chip. An IC that contains a CPU may also contain memory, peripheral interfaces, and other components of a computer; such integrated devices are variously called microcontrollers or systems on a chip (SoC). Some computers employ a multi-core processor, which is a single chip containing two or more CPUs called "cores"; in that context, single chips are sometimes referred to as "sockets".[3] Array processors or vector processors have multiple processors that operate in parallel, with no unit considered central. There also exists the concept of Virtual CPUs which are an abstraction of dynamical aggregated computational resources. [4] The world is a common name for the whole of human civilization, or for the planet Earth and all life upon it.[1] In terms such as world map and world climate, world is used in the sense detached from human culture or civilization, referring to the planet Earth physically. In a philosophical context the term may refer to the whole of the physical Universe, or an ontological world, described by Martin Heidegger as world disclosure. In a theological context, world usually refers to the material or the profane sphere, as opposed to the celestial, spiritual, transcendent or sacred. The "end of the world" refers to scenarios of the final end of human history, often in religious contexts. World history is commonly understood as spanning the major geopolitical developments of about five millennia, from the first civilizations to the present. In terms such as world religion, world language, world government, and world war, world suggests international or intercontinental scope without necessarily implying participation of the entire world. World population is the sum of all human populations at any time; similarly, world economy is the sum of the economies of all societies or countries, especially in the context of globalization. Terms like world championship, gross world product, world flags imply the sum or combination of all current-day sovereign states. A table is an item of furniture with a flat top and one or more legs, used as a surface for working at or on which to place things.[1][2] Some common types of table are the dining room table, which is used for seated persons to eat meals; the coffee table, which is a low table used in living rooms to display items or serve refreshments; and the bedside table, which is used to place an alarm clock and a lamp. Common design elements include: top surfaces of various shapes, including rectangular, square, rounded or semi-circular legs arranged in two or more similar pairs. It usually has four legs. several geometries of folding table that can be collapsed into a smaller volume (e.g., a TV tray, which is a portable, folding table on a stand) heights ranging up and down from the most common 18–30 inches (46–76 cm) range, often reflecting the height of chairs or bar stools used as seating for people making use of a table, as for eating or performing various manipulations of objects resting on a table presence or absence of drawers, shelves or other areas for storing items expansion of the table surface by insertion of leaves or locking hinged drop leaf sections into a horizontal position (this is particularly common for dining tables) Language is the ability to acquire and use complex systems of communication, particularly the human ability to do so, and a language is any specific example of such a system. The scientific study of language is called linguistics. Questions concerning the philosophy of language, such as whether words can represent experience, have been debated since Gorgias and Plato in Ancient Greece. Thinkers such as Rousseau have argued that language originated from emotions while others like Kant have held that it originated from rational and logical thought. 20th-century philosophers such as Wittgenstein argued that philosophy is really the study of language. Major figures in linguistics include Ferdinand de Saussure and Noam Chomsky. Estimates of the number of languages in the world vary between 5,000 and 7,000. However, any precise estimate depends on a partly arbitrary distinction between languages and dialects. Natural languages are spoken or signed, but any language can be encoded into secondary media using auditory, visual, or tactile stimuli – for example, in whistling, signed, or braille. This is because human language is modality-independent. Depending on philosophical perspectives regarding the definition of language and meaning, when used as a general concept, "language" may refer to the cognitive ability to learn and use systems of complex communication, or to describe the set of rules that makes up these systems, or the set of utterances that can be produced from those rules. All languages rely on the process of semiosis to relate signs to particular meanings. Oral and sign languages contain a phonological system that governs how symbols are used to form sequences known as words or morphemes, and a syntactic system that governs how words and morphemes are combined to form phrases and utterances. The metre, or meter (American spelling), (from the Greek noun μέτρον, "measure") is the base unit of length in the International System of Units (SI). The SI unit symbol is m.[1] The metre is defined as the distance travelled by light in a vacuum in 1 / 299 792 458 seconds.[2] The metre was originally defined in 1793 as one ten-millionth of the distance from the equator to the North Pole. In 1799, it was redefined in terms of a prototype metre bar (the actual bar used was changed in 1889 and 1927). In 1960, the metre was redefined in terms of a certain number of wavelengths of a certain emission line of krypton-86. In 1983, the current definition was adopted. The imperial inch is defined as 0.0254 metres (2.54 centimetres or 25.4 millimetres). One metre is about  3 3⁄8 inches longer Gender is the range of characteristics pertaining to, and differentiating between, masculinity and femininity. Depending on the context, these characteristics may include biological sex (i.e. the state of being male, female or intersex), sex-based social structures (including gender roles and other social roles), or gender identity.[1][2][3] Some cultures have specific gender roles that can be considered distinct from male and female, such as the hijra (chhaka) of India and Pakistan. Sexologist John Money introduced the terminological distinction between biological sex and gender as a role in 1955. Before his work, it was uncommon to use the word gender to refer to anything but grammatical categories.[1][2] However, Money's meaning of the word did not become widespread until the 1970s, when feminist theory embraced the concept of a distinction between biological sex and the social construct of gender. Today, the distinction is strictly followed in some contexts, especially the social sciences[4][5] and documents written by the World Health Organization (WHO).[3] In other contexts, including some areas of social sciences, gender includes sex or replaces it.[1][2] For instance, in non-human animal research, gender is commonly used to refer to the biological sex of the animals.[2] This change in the meaning of gender can be traced to the 1980s. In 1993, the USA's Food and Drug Administration (FDA) started to use gender instead of sex.[6] Later, in 2011, the FDA reversed its position and began using sex as the biological classification and gender as "a person's self representation as male or female, or how that person is responded to by social institutions based on the individual's gender presentation."[7] The social sciences have a branch devoted to gender studies. Other sciences, such as sexology and neuroscience, are also interested in the subject. While the social sciences sometimes approach gender as a social construct, and gender studies particularly do, research in the natural sciences investigates whether biological differences in males and females influence the development of gender in humans; both inform debate about how far biological differences influence the formation of gender identity. In the English literature, there is also a trichotomy between biological sex, psychological gender, and social gender role. This framework first appeared in a feminist paper on transsexualism in 1978.[2][8] This article focuses on the collective seas of Earth. For individual seas, see List of seas. For other uses, see Sea (disambiguation), Seas (disambiguation), The Sea (disambiguation), and Ocean Sea (novel). A wave hitting a breakwater in the Gulf of Santa Catalina. Seas are important for human development and trade, as at Singapore, the world's busiest entrepôt. A sea is a large body of salt water that is surrounded in whole or in part by land.[1] More broadly, "the sea" is the interconnected system of Earth's salty, oceanic waters—considered as one global ocean or as several principal oceanic divisions. The sea moderates Earth's climate and has important roles in the water cycle, carbon cycle, and nitrogen cycle. Although the sea has been travelled and explored since prehistory, the modern scientific study of the sea—oceanography—dates broadly to the British Challenger expedition of the 1870s.[2] The sea is conventionally divided into up to five large oceanic sections—including the International Hydrographic Organization's four named oceans[3] (the Atlantic, Pacific, Indian, and Arctic) and the Southern Ocean;[4] smaller, second-order sections, such as the Mediterranean, are known as seas. Owing to the present state of continental drift, the Northern Hemisphere is now fairly equally divided between land and sea (a ratio of about 2:3) but the South is overwhelmingly oceanic (1:4.7).[5] Salinity in the open ocean is generally in a narrow band around 3.5% by mass, although this can vary in more landlocked waters, near the mouths of large rivers, or at great depths. About 85% of the solids in the open sea are sodium chloride. Deep-sea currents are produced by differences in salinity and temperature. Surface currents are formed by the friction of waves produced by the wind and by tides, the changes in local sea level produced by the gravity of the Moon and Sun. The direction of all of these is governed by surface and submarine land masses and by the rotation of the Earth (the Coriolis effect). Former changes in sea levels have left continental shelves, shallow areas in the sea close to land. These nutrient-rich waters teem with life, which provide humans with substantial supplies of food—mainly fish, but also shellfish, mammals, and seaweed—which are both harvested in the wild and farmed. The most diverse areas surround great tropical coral reefs. Whaling in the deep sea was once common but whales' dwindling numbers prompted international conservation efforts and finally a moratorium on most commercial hunting. Oceanography has established that not all life is restricted to the sunlit surface waters: even under enormous depths and pressures, nutrients streaming from hydrothermal vents support their own unique ecosystem. Life may have started there and aquatic microbial mats are generally credited with the oxygenation of Earth's atmosphere; both plants and animals first evolved in the sea. Ambiguity means confusion about what is conveyed, since the current context may lead to different interpretations of meaning. Many words in many languages have multiple definitions. Ambiguity is an effect of a rupture of the rule of identity in the context of the exchange of information. Particularly the sender may be physically absent, and the contexts explicitly divergent, such as will be the case when the receptor is a reader and the sender was a writer. Pragmatics[edit] Main article: Pragmatics Pragmatics is the study of how context affects meaning. The two primary forms of context important to pragmatics are linguistic context and situation context. Linguistic context is how meaning is understood without relying on intent and assumptions. In applied pragmatics, for example, meaning is formed through sensory experiences, even though sensory stimulus cannot be easily articulated in language or signs. Pragmatics, then, reveals that meaning is both something affected by and affecting the world. Meaning is something contextual with respect to language and the world, and is also something active toward other meanings and the world. Linguistic context becomes important when looking at particular linguistic problems such as that of pronouns. Situation context refers to every non-linguistic factor that affects the meaning of a phrase. An example of situation context can be seen in the phrase "it's cold in here", which can either be a simple statement of fact or a request to turn up the heat, depending on, among other things, whether or not it is believed to be in the listener's power to affect the temperature. his article is about Earth's sky. For other skies, see extraterrestrial skies. For other uses, see Sky (disambiguation). The sky above the clouds The sky (or celestial dome) is everything that lies above the surface of the Earth, including the atmosphere and outer space. In the field of astronomy, the sky is also called the celestial sphere. This is viewed from Earth's surface as an imaginary dome where the sun, stars, planets, and the moon are seen to be traveling. The celestial sphere is conventionally divided into regions called constellations. Usually, the term sky is used informally as the point of view from the Earth's surface; however, the meaning and usage can vary. In some cases, such as in discussing the weather, the sky refers to only the lower, more dense portions of the atmosphere. During daylight, the sky appears to be blue because air scatters blue sunlight more than it scatters red.[1][2][3][4] At night, the sky appears to be a mostly dark surface or region scattered with stars. During the day, the Sun can be seen in the sky unless obscured by clouds. In the night sky (and to some extent during the day) the moon, planets and stars are visible in the sky. Some of the natural phenomena seen in the sky are clouds, rainbows, and aurorae. Lightning and precipitation can also be seen in the sky during storms. Birds, insects, aircraft, and kites are often considered to fly in the sky. Due to human activities, smog during the day and light pollution during the night are often seen above large cities. Quantity is a property that can exist as a magnitude or multitude. Quantities can be compared in terms of "more", "less", or "equal", or by assigning a numerical value in terms of a unit of measurement. Quantity is among the basic classes of things along with quality, substance, change, and relation. Some quantities are such by their inner nature (as number), while others are functioning as states (properties, dimensions, attributes) of things such as heavy and light, long and short, broad and narrow, small and great, or much and little. A small quantity is sometimes referred to as a quantulum. Multicultural sign of quantity, refers to the simplest way of accounting - by sticks. Three sticks - the initial indicator of multiplicity as the first odd prime number. Two basic divisions of quantity, magnitude and multitude, imply the principal distinction between continuity (continuum) and discontinuity. Under the name of multitude come what is discontinuous and discrete and divisible into indivisibles, all cases of collective nouns: army, fleet, flock, government, company, party, people, chorus, crowd, mess, and number. Under the name of magnitude come what is continuous and unified and divisible into divisibles, all cases of non-collective nouns: the universe, matter, mass, energy, liquid, material, animal, plant, tree. Along with analyzing its nature and classification, the issues of quantity involve such closely related topics as the relation of magnitudes and multitudes, dimensionality, equality, proportion, the measurements of quantities, the units of measurements, number and numbering systems, the types of numbers and their relations to each other as numerical ratios. Thus quantity is a property that exists in a range of magnitudes or multitudes. Mass, time, distance, heat, and angular separation are among the familiar examples of quantitative properties. Two magnitudes of a continuous quantity stand in relation to one another as a ratio which is a real number. Background[edit] In mathematics the concept of quantity is an ancient one extending back to the time of Aristotle and earlier. Aristotle regarded quantity as a fundamental ontological and scientific category. In Aristotle's ontology, quantity or quantum was classified into two different types, which he characterized as follows: 'Quantum' means that which is divisible into two or more constituent parts, of which each is by nature a 'one' and a 'this'. A quantum is a plurality if it is numerable, a magnitude if it is measurable. 'Plurality' means that which is divisible potentially into non-continuous parts, magnitude that which is divisible into continuous parts; of magnitude, that which is continuous in one dimension is length; in two breadth, in three depth. Of these, limited plurality is number, limited length is a line, breadth a surface, depth a solid. (Aristotle, book v, chapters 11-14, Metaphysics). In his Elements, Euclid developed the theory of ratios of magnitudes without studying the nature of magnitudes, as Archimedes, but giving the following significant definitions: A magnitude is a part of a magnitude, the less of the greater, when it measures the greater; A ratio is a sort of relation in respect of size between two magnitudes of the same kind. For Aristotle and Euclid, relations were conceived as whole numbers (Michell, 1993). John Wallis later conceived of ratios of magnitudes as real numbers as reflected in the following: When a comparison in terms of ratio is made, the resultant ratio often [namely with the exception of the 'numerical genus' itself] leaves the genus of quantities compared, and passes into the numerical genus, whatever the genus of quantities compared may have been. (John Wallis, Mathesis Universalis) That is, the ratio of magnitudes of any quantity, whether volume, mass, heat and so on, is a number. Following this, Newton then defined number, and the relationship between quantity and number, in the following terms: "By number we understand not so much a multitude of unities, as the abstracted ratio of any quantity to another quantity of the same kind, which we take for unity" (Newton, 1728). Quantitative structure[edit] Continuous quantities possess a particular structure that was first explicitly characterized by Hölder (1901) as a set of axioms that define such features as identities and relations between magnitudes. In science, quantitative structure is the subject of empirical investigation and cannot be assumed to exist a priori for any given property. The linear continuum represents the prototype of continuous quantitative structure as characterized by Hölder (1901) (translated in Michell & Ernst, 1996). A fundamental feature of any type of quantity is that the relationships of equality or inequality can in principle be stated in comparisons between particular magnitudes, unlike quality, which is marked by likeness, similarity and difference, diversity. Another fundamental feature is additivity. Additivity may involve concatenation, such as adding two lengths A and B to obtain a third A + B. Additivity is not, however, restricted to extensive quantities but may also entail relations between magnitudes that can be established through experiments that permit tests of hypothesized observable manifestations of the additive relations of magnitudes. Another feature is continuity, on which Michell (1999, p. 51) says of length, as a type of quantitative attribute, "what continuity means is that if any arbitrary length, a, is selected as a unit, then for every positive real number, r, there is a length b such that b = ra". A further generalization is given by the theory of conjoint measurement, independently developed by French economist Gérard Debreu (1960) and by the American mathematical psychologist R. Duncan Luce and statistician John Tukey (1964). Padding From Wikipedia, the free encyclopedia This article is about clothing. For other uses of the term, see Padding (disambiguation). Padding is thin cushioned material sometimes added to clothes. It is often done in an attempt to soften impacts on certain zones of the body or enhance appearance by 'improving' a physical feature, often a sexually significant one. In fashion, there is padding for: Breasts – sometimes called falsies The male crotch – usually called a codpiece. Height – usually in shoes and often called elevator shoes. Width of shoulders, called shoulder pads – in coats and other garments for men, and sometimes for women. To alter features[edit] Some padding is added to emphasize particular physical features that are usually not present. Women, for instance, rarely have prominent shoulders, but for some years shoulder pads have been added to dresses (blouses, etc.). The effect was unnatural for women, but gave them a more masculine outline which was sometimes thought to be of benefit in business situations. Padding in undergarments is also used by some crossdressers. This may include a form of padding in the shape of male genitals worn in the underwear of a female who is passing as a male, or hip and buttock padding worn by a male who is passing as a female. As protection[edit] Padding is also added to clothing for insulation or cushioning reasons. Thus, many coats and outergarments (especially those for outdoor use in cold climates) are padded with such materials as felt or down or feathers or artificial insulations. Cushioning padding is included in some sporting goods, especially those intended for use in combat sports (e.g., fencing, some martial arts, etc.). Garments intended for actual use in combat were once commonly padded (e.g., by the ancient Greeks under armor, or by the Japanese until the mid-19th century), but have largely been replaced by light armor made of, for instance, Kevlar. If included in a vest, such armor makes a bullet-proof vest. Look up padding in Wiktionary, the free dictionary. For other uses, see Emotion (disambiguation). "Emotional" redirects here. For other uses, see Emotional (disambiguation). Part of a series on Emotions Affection Anger Angst Anguish Annoyance Anticipation Anxiety Apathy Arousal Awe Boredom Confidence Contempt Contentment Courage Curiosity Depression Desire Despair Disappointment Disgust Distrust Ecstasy Embarrassment Empathy Envy Euphoria Fear Frustration Gratitude Grief Guilt Happiness Hatred Hope Horror Hostility Humiliation Hysteria Interest Jealousy Joy Loneliness Love Lust Outrage Panic Passion Pity Pleasure Pride Rage Regret Remorse Resentment Sadness Saudade Schadenfreude Self-confidence Shame Shock Shyness Sorrow Suffering Surprise Trust Wonder Worry v t e Emotion, in everyday speech, is any relatively brief conscious experience characterized by intense mental activity and a high degree of pleasure or displeasure.[1][2] Scientific discourse has drifted to other meanings and there is no consensus on a definition. Emotion is often intertwined with mood, temperament, personality, disposition, and motivation.[3] In some theories, cognition is an important aspect of emotion. Those acting primarily on the emotions they are feeling may seem as if they are not thinking, but mental processes are still essential, particularly in the interpretation of events. For example, the realization of our believing that we are in a dangerous situation and the subsequent arousal of our body's nervous system (rapid heartbeat and breathing, sweating, muscle tension) is integral to the experience of our feeling afraid. Other theories, however, claim that emotion is separate from and can precede cognition. Emotions are complex. According to some theories, they are a state of feeling that results in physical and psychological changes that influence our behavior.[2] The physiology of emotion is closely linked to arousal of the nervous system with various states and strengths of arousal relating, apparently, to particular emotions. Emotion is also linked to behavioral tendency. Extroverted people are more likely to be social and express their emotions, while introverted people are more likely to be more socially withdrawn and conceal their emotions. Emotion is often the driving force behind motivation, positive or negative.[4] According to other theories, emotions are not causal forces but simply syndromes of components, which might include motivation, feeling, behavior, and physiological changes, but no one of these components is the emotion. Nor is the emotion an entity that causes these components.[5] Emotions involve different components, such as subjective experience, cognitive processes, expressive behavior, psychophysiological changes, and instrumental behavior. At one time, academics attempted to identify the emotion with one of the components: William James with a subjective experience, behaviorists with instrumental behavior, psychophysiologists with physiological changes, and so on. More recently, emotion is said to consist of all the components. The different components of emotion are categorized somewhat differently depending on the academic discipline. In psychology and philosophy, emotion typically includes a subjective, conscious experience characterized primarily by psychophysiological expressions, biological reactions, and mental states. A similar multicomponential description of emotion is found in sociology. For example, Peggy Thoits[6] described emotions as involving physiological components, cultural or emotional labels (anger, surprise, etc.), expressive body actions, and the appraisal of situations and contexts. Research on emotion has increased significantly over the past two decades with many fields contributing including psychology, neuroscience, endocrinology, medicine, history, sociology, and computer science. The numerous theories that attempt to explain the origin, neurobiology, experience, and function of emotions have only fostered more intense research on this topic. Current areas of research in the concept of emotion include the development of materials that stimulate and elicit emotion. In addition PET scans and fMRI scans help study the affective processes in the brain.[7] For other uses, see Sanity (disambiguation). "Sound mind" redirects here. For the phrase "sound mind in a sound body", see Mens sana in corpore sano. Sanity (from Latin: sānitās) refers to the soundness, rationality and healthiness of the human mind, as opposed to insanity. A person is not considered sane anymore just if he/she is irrational. In modern society, the terms have become exclusively synonymous with compos mentis (Latin: compos, having mastery of, and mentis, mind), in contrast with non compos mentis, or insane, meaning troubled conscience. A sane mind is nowadays considered healthy both from its analytical -once called rational- and emotional aspects.[1] Furthermore, according to Chesterton,[2] sanity involves wholeness, whereas insanity implies narrowness and brokenness. Contents [hide] 1 Psychiatry and psychology 2 Law 3 See also 4 References Psychiatry and psychology[edit] A theory of sanity was proposed by Alfred Korzybski in his general semantics. He believed sanity was tied to the structural fit or lack of thereof, of what is actually going on in the world. He imposed this notion in a map-territory analogy: "A map is not the territory it represents, but, if correct, it has a "similar structure" to the territory, which accounts for its usefulness."[3] Given that science continually seeks to adjust its theories structurally to fit the facts, i.e., adjusts its maps to fit the territory, and thus advances more rapidly than any other field, he believed that the key to understanding sanity would be found in the study of the methods of science (and the study of structure as revealed by science). The adoption of a scientific outlook and attitude of continual adjustment by the individual toward his or her assumptions was the way, so he claimed. In other words, there were "factors of sanity to be found in the physico-mathematical methods of science." And he also stressed that sanity requires the awareness that "whatever you say a thing is, it is not"[4] because anything expressed through language is not the reality it refers to: language is like a map and the map is not the territory. The territory, that is, reality, remains unnamable, un-speakable, mysterious. Hence, the widespread assumption that we can grasp reality through language involves a degree of insanity. Psychiatrist Philip S. Graven suggested the term "un-sane" to describe a condition that is not exactly insane, but not quite sane either.[5] In The Sane Society, published in 1955, psychologist Erich Fromm proposed that, not just individuals, but entire societies "may be lacking in sanity". Fromm argued that one of the most deceptive features of social life involves "consensual validation":[6] Semantics (from Ancient Greek: σημαντικός sēmantikos, "significant")[1][2] is primarily the linguistic, and also philosophical study of meaning—in language, programming languages, formal logics, and semiotics. It focuses on the relationship between signifiers—like words, phrases, signs, and symbols—and what they stand for, their denotation. In international scientific vocabulary semantics is also called semasiology. The word semantics was first used by Michel Bréal, a French philologist.[3] It denotes a range of ideas—from the popular to the highly technical. It is often used in ordinary language for denoting a problem of understanding that comes down to word selection or connotation. This problem of understanding has been the subject of many formal enquiries, over a long period of time, especially in the field of formal semantics. In linguistics, it is the study of the interpretation of signs or symbols used in agents or communities within particular circumstances and contexts.[4] Within this view, sounds, facial expressions, body language, and proxemics have semantic (meaningful) content, and each comprises several branches of study. In written language, things like paragraph structure and punctuation bear semantic content; other forms of language bear other semantic content.[4] The formal study of semantics intersects with many other fields of inquiry, including lexicology, syntax, pragmatics, etymology and others. Independently, semantics is also a well-defined field in its own right, often with synthetic properties.[5] In the philosophy of language, semantics and reference are closely connected. Further related fields include philology, communication, and semiotics. The formal study of semantics can therefore be manifold and complex. Semantics contrasts with syntax, the study of the combinatorics of units of a language (without reference to their meaning), and pragmatics, the study of the relationships between the symbols of a language, their meaning, and the users of the language.[6] Semantics as a field of study also has significant ties to various representational theories of meaning including truth theories of meaning, coherence theories of meaning, and correspondence theories of meaning. Each of these is related to the general philosophical study of reality and the representation of meaning. This article is about mechanical robots. For software agents, see Bot. For other uses of the term, see Robot (disambiguation). ASIMO (2000) at the Expo 2005, a bipedal humanoid robot. Articulated welding robots used in a factory, a type of industrial robot. The quadrupedal military robot Cheetah, an evolution of BigDog (pictured), was clocked as the world's fastest legged robot in 2012, beating the record set by an MIT bipedal robot in 1989.[1] A robot is a mechanical or virtual artificial agent, usually an electromechanical machine that is guided by a computer program or electronic circuitry, and thus a type of an embedded system. Robots can be autonomous or semi-autonomous and range from humanoids such as Honda's Advanced Step in Innovative Mobility (ASIMO) and TOSY's TOSY Ping Pong Playing Robot (TOPIO) to industrial robots, medical operating robots, patent assist robots, dog therapy robots, collectively programmed swarm robots, UAV drones such as General Atomics MQ-1 Predator, and even microscopic nano robots. By mimicking a lifelike appearance or automating movements, a robot may convey a sense of intelligence or thought of its own. The branch of technology that deals with the design, construction, operation, and application of robots,[2] as well as computer systems for their control, sensory feedback, and information processing is robotics. These technologies deal with automated machines that can take the place of humans in dangerous environments or manufacturing processes, or resemble humans in appearance, behavior, and/or cognition. Many of today's robots are inspired by nature contributing to the field of bio-inspired robotics. These robots have also created a newer branch of robotics: soft robotics. From the time of ancient civilization there have been many accounts of user-configurable automated devices and even automata resembling animals and humans, designed primarily as entertainment. As mechanical techniques developed through the Industrial age, there appeared more practical applications such as automated machines, remote-control and wireless remote-control. The word 'robot' was first used to denote a fictional humanoid in a 1920 play R.U.R. by the Czech writer, Karel Čapek but it was Karel's brother Josef Čapek who was the word's true inventor.[3][4] Electronics evolved into the driving force of development with the advent of the first electronic autonomous robots created by William Grey Walter in Bristol, England in 1948. The first digital and programmable robot was invented by George Devol in 1954 and was named the Unimate. It was sold to General Motors in 1961 where it was used to lift pieces of hot metal from die casting machines at the Inland Fisher Guide Plant in the West Trenton section of Ewing Township, New Jersey.[5] Robots have replaced humans[6] in performing repetitive and dangerous tasks which humans prefer not to do, or are unable to do because of size limitations, or which take place in extreme environments such as outer space or the bottom of the sea. There are concerns about the increasing use of robots and their role in society. Robots are blamed for rising unemployment as they replace workers in increasing numbers of functions.[7] The use of robots in military combat raises ethical concerns. The possibilities of robot autonomy and potential repercussions have been addressed in fiction and may be a realistic concern in the This article is about the American system. It is not to be confused with the Russian equivalent (GLONASS), the Indian equivalent (IRNSS), other similar systems (GNSS), the Chinese equivalent (BeiDou-2tf), or the European equivalent (GALILEO). "GPS" redirects here. For the device, see GPS receiver. For other uses, see GPS (disambiguation). Global Positioning System Country of origin United States Operator(s) AFSPC Type Military, civilian Status Operational Coverage Global Precision 5 meters Constellation size Total satellites 32 Satellites in orbit 31 First launch February 1978; 38 years ago Total launches 72 Orbital characteristics Regime(s) 6x MEO planes Orbital height 20,180 km (12,540 mi) Geodesy Fundamentals Geodesy Geodynamics Geomatics Cartography History Concepts Geographical distance Geoid Figure of the Earth Geodetic datum Geodesic Geographic coordinate system Horizontal position representation Latitude / Longitude Map projection Reference ellipsoid Satellite geodesy Spatial reference system Technologies Global Navigation Satellite System (GNSS) Global Positioning System (GPS) GLONASS (Russian) BeiDou (BDS) (Chinese) Galileo (European) Indian Regional Navigation Satellite System (IRNSS) Standards ED50 European Datum 1950 SAD69 South American Datum 1969 GRS 80 Geodetic Reference System 1980 NAD83 North American Datum 1983 WGS84 World Geodetic System 1984 NAVD88 N. American Vertical Datum 1988 ETRS89 European Terrestrial Reference System 1989 GCJ-02 Chinese encrypted datum 2002 International Terrestrial Reference System Spatial Reference System Identifier (SRID) Universal Transverse Mercator (UTM) History NGVD29 (Sea Level Datum 1929) v t e Artist's conception of GPS Block II-F satellite in Earth orbit. Civilian GPS receivers ("GPS navigation device") in a marine application. Automotive navigation system in a taxicab. A U.S. Air Force Senior Airman runs through a checklist during Global Positioning System satellite operations. The Global Positioning System (GPS), also known as Navstar,[1] is a global navigation satellite system (GNSS) that provides location and time information in all weather conditions, anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites.[2] The GPS system operates independently of any telephonic or internet reception, though these technologies can enhance the usefulness of the GPS positioning information. The GPS system provides critical positioning capabilities to military, civil, and commercial users around the world. The United States government created the system, maintains it, and makes it freely accessible to anyone with a GPS receiver. The GPS project was launched in the United States in 1973 to overcome the limitations of previous navigation systems,[3] integrating ideas from several predecessors, including a number of classified engineering design studies from the 1960s. The U.S. Department of Defense (DoD) developed the system, which originally used 24 satellites. It became fully operational in 1995. Roger L. Easton, Ivan A. Getting and Bradford Parkinson of the Applied Physics Laboratory are credited with inventing it.[4] Advances in technology and new demands on the existing system have now led to efforts to modernize the GPS and implement the next generation of GPS Block IIIA satellites and Next Generation Operational Control System (OCX).[5] Announcements from Vice President Al Gore and the White House in 1998 initiated these changes. In 2000, the U.S. Congress authorized the modernization effort, GPS III. In addition to GPS, other systems are in use or under development. The Russian Global Navigation Satellite System (GLONASS) was developed contemporaneously with GPS, but suffered from incomplete coverage of the globe until the mid-2000s.[6] There are also the planned European Union Galileo positioning system, China's BeiDou Navigation Satellite System, the Japanese Quasi-Zenith Satellite System, and India's Indian Regional Navigation Satellite System. A boat is a watercraft of a large range of sizes designed to float, plane, work or travel on water. Small boats are typically found on inland waterways (e.g., rivers and lakes) or in protected coastal areas. However, boats such as the whaleboat were designed for operation from a ship in an offshore environment. In naval terms, a boat is a vessel small enough to be carried aboard another vessel (a ship). Another less restrictive definition is a vessel that can be lifted out of the water. Some definitions do not make a distinction in size, as bulk freighters 1,000 feet (300 m) long on the Great Lakes are called oreboats. For reasons of naval tradition, submarines are usually referred to as 'boats' rather than 'ships', regardless of their size and shape. Ships are generally distinguished from boats based on their larger size, shape and cargo or passenger capacity. Boats have a wide variety of shapes, sizes and construction methods due to their intended purpose, available materials or local traditions. Canoe-type boats have been used since prehistoric times and various versions are used throughout the world for transportation, fishing or sport. Fishing boats vary widely in style partly to match local conditions. Pleasure boats include ski boats, pontoon boats, and sailboats. House boats may be used for vacationing or long-term housing. Small boats can provide transport or convey cargo (lightering) to and from large ships. Lifeboats have rescue and safety functions. Boats can be powered by human power (e.g., rowboats), wind power (e.g., sailboats) and motor power (e.g., propellor-driven motorboats driven by gasoline or diesel engines). A fish is any member of a group of organisms that consist of all gill-bearing aquatic craniate animals that lack limbs with digits. They form a sister group to the tunicates, together forming the olfactores. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups. Tetrapods emerged within lobe-finned fishes, so cladistically they are fish as well. However, traditionally fish are rendered paraphyletic by excluding the tetrapods (i.e., the amphibians, reptiles, birds and mammals which all descended from within the same ancestry). Because in this manner the term "fish" is defined negatively as a paraphyletic group, it is not considered a formal taxonomic grouping in systematic biology. The traditional term pisces (also ichthyes) is considered a typological, but not a phylogenetic classification. The earliest organisms that can be classified as fish were soft-bodied chordates that first appeared during the Cambrian period. Although they lacked a true spine, they possessed notochords which allowed them to be more agile than their invertebrate counterparts. Fish would continue to evolve through the Paleozoic era, diversifying into a wide variety of forms. Many fish of the Paleozoic developed external armor that protected them from predators. The first fish with jaws appeared in the Silurian period, after which many (such as sharks) became formidable marine predators rather than just the prey of arthropods. Most fish are ectothermic ("cold-blooded"), allowing their body temperatures to vary as ambient temperatures change, though some of the large active swimmers like white shark and tuna can hold a higher core temperature.[1][2] Fish are abundant in most bodies of water. They can be found in nearly all aquatic environments, from high mountain streams (e.g., char and gudgeon) to the abyssal and even hadal depths of the deepest oceans (e.g., gulpers and anglerfish). With 33,100 described species, fish exhibit greater species diversity than any other group of vertebrates.[3] Fish are an important resource for humans worldwide, especially as food. Commercial and subsistence fishers hunt fish in wild fisheries (see fishing) or farm them in ponds or in cages in the ocean (see aquaculture). They are also caught by recreational fishers, kept as pets, raised by fishkeepers, and exhibited in public aquaria. Fish have had a role in culture through the ages, serving as deities, religious symbols, and as the subjects of art, books and movies. For the plant genus, see Nicotiana. For the American electronic musician, see Tobacco (musician). Not to be confused with Tabacco. Tobacco Tobacco can also be pressed into plugs and sliced into flakes. Botanical name Tobacco Source plant(s) Nicotiana Part(s) of plant leaf Geographic origin South America Active ingredients Nicotine, harmine Uses Recreational Legal status AU: Unscheduled CA: Unscheduled UK: Unscheduled US: 18+ only UN: Unscheduled EU: Unscheduled see tobacco control A historic kiln in Myrtleford, Victoria, Australia Basma tobacco leaves drying in the sun at Pomak village in Xanthi, Greece Tobacco is a product prepared from the leaves of the tobacco plant by curing them. The plant is part of the genus Nicotiana and of the Solanaceae (nightshade) family. While more than 70 species of tobacco are known, the chief commercial crop is N. tabacum. The more potent variant N. rustica is also used around the world. Tobacco contains the alkaloid nicotine, which is a stimulant. Dried tobacco leaves are mainly used for smoking in cigarettes, cigars, pipe tobacco, and flavored shisha tobacco. They can be also consumed as snuff, chewing tobacco, dipping tobacco and snus. Tobacco use is a risk factor for many diseases, especially those affecting the heart, liver, and lungs, as well as many cancers. In 2008, the World Health Organization named tobacco as the world's single greatest cause of preventable death.[1] An army (from Latin arma "arms, weapons" via Old French armée, "armed" (feminine)) or ground force is a fighting force that fights primarily on land. In the broadest sense, it is the land-based military branch, service branch or armed service of a nation or state. It may also include other branches of the military such as the air force via means of aviation corps. Within a national military force, the word army may also mean a field army. They differ from army reserves who are activated only during such times as war or natural disasters. In several countries, the army is officially called the Land Army to differentiate it from an air force called the Air Army, notably France. In such countries, the word "army" on its own retains its connotation of a land force in common usage. The current largest army in the world, by number of active troops, is the People's Liberation Army Ground Force of China with 1,600,000 active troops and 510,000 reserve personnel followed by the Indian Army with 1,129,000 active troops and 960,000 reserve personnel. By convention, irregular military is understood in contrast to regular armies which grew slowly from personal bodyguards or elite militia. Regular in this case refers to standardized doctrines, uniforms, organizations, etc. Regular military can also refer to full-time status (standing army), versus reserve or part-time personnel. Other distinctions may separate statutory forces (established under laws such as the National Defence Act), from de facto "non-statutory" forces such as some guerrilla and revolutionary armies. Armies may also be expeditionary (designed for overseas or international deployment) or fencible (designed for – or restricted to – homeland defence).