Analog computer
An analog computer or analogue computer is a type of computer that uses the continuously changeable aspects of physical phenomena such as electrical, mechanical, or hydraulic quantities to model the problem being solved. In contrast, digital computers represent varying quantities symbolically, as their numerical values change; as an analog computer does not use discrete values, but rather continuous values, processes cannot be reliably repeated with exact equivalence, as they can with Turing machines. Unlike machines used for digital signal processing, analog computers do not suffer from the discrete error caused by quantization noise. Instead, results from analog computers are subject to continuous error caused by electronic noise. Analog computers were used in scientific and industrial applications where digital computers of the time lacked sufficient performance. Analog computers can have a wide range of complexity. Slide rules and nomograms are the simplest, while naval gunfire control computers and large hybrid digital/analog computers were among the most complicated.
Systems for process control and protective relays used analog computation to perform control and protective functions. The advent of digital computing made simple analog computers obsolete as early as the 1950s and 1960s, although analog computers remained in use in some specific applications, like the flight computer in aircraft, for teaching control systems in universities. More complex applications, such as synthetic aperture radar, remained the domain of analog computing well into the 1980s, since digital computers were insufficient for the task. Setting up an analog computer required scale factors to be chosen, along with initial conditions—that is, starting values. Another essential was creating the required network of interconnections between computing elements. Sometimes it was necessary to re-think the structure of the problem so that the computer would function satisfactorily. No variables could be allowed to exceed the computer's limits, differentiation was to be avoided by rearranging the "network" of interconnects, using integrators in a different sense.
Running an electronic analog computer, assuming a satisfactory setup, started with the computer held with some variables fixed at their initial values. Moving a switch released the holds and permitted the problem to run. In some instances, the computer could, after a certain running time interval return to the initial-conditions state to reset the problem, run it again; this is a list of examples of early computation devices which are considered to be precursors of the modern computers. Some of them may have been dubbed as'computers' by the press, although they may fail to fit the modern definitions; the south-pointing chariot, invented in ancient China during the first millennium BC, can be considered the earliest analog computer. It was a mechanical-geared wheeled vehicle used to discern the southern cardinal direction; the Antikythera mechanism was an orrery and is claimed to be an early mechanical analog computer, according to Derek J. de Solla Price. It was designed to calculate astronomical positions.
It was discovered in 1901 in the Antikythera wreck off the Greek island of Antikythera, between Kythera and Crete, has been dated to circa 100 BC. Devices of a level of complexity comparable to that of the Antikythera mechanism would not reappear until a thousand years later. Many mechanical aids to calculation and measurement were constructed for astronomical and navigation use; the planisphere was a star chart invented by Abū Rayḥān al-Bīrūnī in the early 11th century. The astrolabe was invented in the Hellenistic world in either the 1st or 2nd centuries BC and is attributed to Hipparchus. A combination of the planisphere and dioptra, the astrolabe was an analog computer capable of working out several different kinds of problems in spherical astronomy. An astrolabe incorporating a mechanical calendar computer and gear-wheels was invented by Abi Bakr of Isfahan, Persia in 1235. Abū Rayhān al-Bīrūnī invented the first mechanical geared lunisolar calendar astrolabe, an early fixed-wired knowledge processing machine with a gear train and gear-wheels, circa 1000 AD.
The castle clock, a hydropowered mechanical astronomical clock invented by Al-Jazari in 1206, was the first programmable analog computer. The sector, a calculating instrument used for solving problems in proportion, trigonometry and division, for various functions, such as squares and cube roots, was developed in the late 16th century and found application in gunnery and navigation; the planimeter was a manual instrument to calculate the area of a closed figure by tracing over it with a mechanical linkage. The slide rule was invented around 1620–1630, shortly after the publication of the concept of the logarithm, it is a hand-operated analog computer for doing division. As slide rule development progressed, added scales provided reciprocals and square roots and cube roots, as well as transcendental functions such as logarithms and exponentials and hyperbolic trigonometry and other functions. Aviation is one of the few fields where slide rules are still in widespread use for solving time–distance problems in light aircraft.
Mathematician and engineer Giovanni Plana devised a Perpetual Calendar machine which, though a system of pulleys and cylinders and over, could predict the perpetual calendar for every year from 0AD to 4000AD, keeping track of leap years and varying day length. The tide-predicting machine invented by Sir William Thomson in 1872 was of great utility to navigation in shallow waters, it used a system of pulleys and wires to automatically calculate predicted tide levels for a set period at a particular location. The di
Draughts
Draughts or checkers is a group of strategy board games for two players which involve diagonal moves of uniform game pieces and mandatory captures by jumping over opponent pieces. Draughts developed from alquerque; the name derives from the verb to move. The most popular forms are English draughts called American checkers, played on an 8×8 checkerboard. There are many other variants played on 8×8 boards. Canadian checkers and Singaporean/Malaysian checkers are played on a 12×12 board; the 8×8 variant of draughts was weakly solved in 2007 by the team of Canadian computer scientist Jonathan Schaeffer. From the standard starting position, both players can guarantee a draw with perfect play. Draughts is played on opposite sides of the gameboard. One player has the dark pieces. Players alternate turns. A player may not move an opponent's piece. A move consists of moving a piece diagonally to an adjacent unoccupied square. If the adjacent square contains an opponent's piece, the square beyond it is vacant, the piece may be captured by jumping over it.
Only the dark squares of the checkered board are used. A piece may move only diagonally into an unoccupied square; when presented, capturing is mandatory in most official rules, although some rule variations make capturing optional. In all variants, the player without pieces remaining, or who cannot move due to being blocked, loses the game. Uncrowned pieces move one step diagonally forwards, capture an opponent's piece by moving two consecutive steps in the same line, jumping over the piece on the first step. Multiple enemy pieces can be captured in a single turn provided this is done by successive jumps made by a single piece. In English draughts men can jump only forwards; when a man reaches the kings row, it becomes a king, is marked by placing an additional piece on top of the first man, acquires additional powers including the ability to move backwards and capture backwards. Like men, a king can make successive jumps in a single turn provided that each jump captures an enemy man or king.
In international draughts, kings move any distance along unblocked diagonals, may capture an opposing man any distance away by jumping to any of the unoccupied squares beyond it. Because jumped pieces remain on the board until the turn is complete, it is possible to reach a position in a multi-jump move where the flying king is blocked from capturing further by a piece jumped. Flying kings are not used in English draughts. In most non-English languages, draughts is called dame, damas, or a similar term that refers to ladies; the pieces are called men, stones, "peón" or a similar term. In these languages, the queen in chess or in card games is called by the same term as the kings in draughts. A case in point includes the Greek terminology, in which draughts is called "ντάμα", one term for the queen in chess; the World Championship in English draughts began in 1840. The winners in men's have been from the United Kingdom, United States and most Italy; the women's championship in English draughts started in 1993.
The women's winners have been from Ireland and Ukraine. The World Championship in international draughts began in 1885 in France, since 1948 has been organized by the World Draughts Federation, it occurs every two years. In years following the tournament, the World Title match takes place; the men's championship has had winners from the Netherlands, the Soviet Union, Senegal and Russia. The first Women's World Championship was held in 1973; the World Junior Championship has been played since 1971. European Championships have been held since 1965 and 2000. Other official World Championships began as follows: Brazilian draughts, in 1985. Blue and Gray: On a 9×9 board, each side has 17 guard pieces that move and jump in any direction, to escort a captain piece which races to the center of the board to win. Cheskers: A variant invented by Solomon Golomb; each player begins with a bishop and a camel, men reaching the back rank promote to a bishop, camel, or king. Damath: A variant utilizing math principles and numbered chips popular in the Philippines.
Dameo: A variant played on an 8×8 board and capture rules are similar to those of Armenian draughts. A special "sliding" move is used for moving a line of checkers similar to the movement rule in Epaminondas. By Christian Freeling. Hexdame: A literal adaptation of international draughts to a hexagonal gameboard. By Christian Freeling. Lasca: A checkers variant on a 7×7 board, with 25 fields used. Jumped pieces are placed under the jumper. Only the top piece of a jumped; this variant was invented by World Chess Champion Emanuel Lasker. Philosophy shogi checkers: A variant on a 9×9 board, game endi
Vacuum tube
In electronics, a vacuum tube, an electron tube, or valve or, colloquially, a tube, is a device that controls electric current flow in a high vacuum between electrodes to which an electric potential difference has been applied. The type known as a thermionic tube or thermionic valve uses the phenomenon of thermionic emission of electrons from a heated cathode and is used for a number of fundamental electronic functions such as signal amplification and current rectification. Non-thermionic types, such as a vacuum phototube however, achieve electron emission through the photoelectric effect, are used for such as the detection of light levels. In both types, the electrons are accelerated from the cathode to the anode by the electric field in the tube; the simplest vacuum tube, the diode invented in 1904 by John Ambrose Fleming, contains only a heated electron-emitting cathode and an anode. Current can only flow in one direction through the device—from the cathode to the anode. Adding one or more control grids within the tube allows the current between the cathode and anode to be controlled by the voltage on the grid or grids.
These devices became a key component of electronic circuits for the first half of the twentieth century. They were crucial to the development of radio, radar, sound recording and reproduction, long distance telephone networks, analogue and early digital computers. Although some applications had used earlier technologies such as the spark gap transmitter for radio or mechanical computers for computing, it was the invention of the thermionic vacuum tube that made these technologies widespread and practical, created the discipline of electronics. In the 1940s the invention of semiconductor devices made it possible to produce solid-state devices, which are smaller, more efficient and durable, cheaper than thermionic tubes. From the mid-1960s, thermionic tubes were being replaced with the transistor. However, the cathode-ray tube remained the basis for television monitors and oscilloscopes until the early 21st century. Thermionic tubes still have some applications, such as the magnetron used in microwave ovens, certain high-frequency amplifiers, amplifiers that audio enthusiasts prefer for their tube sound.
Not all electronic circuit valves/electron tubes are vacuum tubes. Gas-filled tubes are similar devices, but containing a gas at low pressure, which exploit phenomena related to electric discharge in gases without a heater. One classification of thermionic vacuum tubes is by the number of active electrodes. A device with two active elements is a diode used for rectification. Devices with three elements are triodes used for switching. Additional electrodes create tetrodes, so forth, which have multiple additional functions made possible by the additional controllable electrodes. Other classifications are: by frequency range by power rating by cathode/filament type and Warm-up time by characteristic curves design by application specialized parameters specialized functions tubes used to display information Tubes have different functions, such as cathode ray tubes which create a beam of electrons for display purposes in addition to more specialized functions such as electron microscopy and electron beam lithography.
X-ray tubes are vacuum tubes. Phototubes and photomultipliers rely on electron flow through a vacuum, though in those cases electron emission from the cathode depends on energy from photons rather than thermionic emission. Since these sorts of "vacuum tubes" have functions other than electronic amplification and rectification they are described in their own articles. A vacuum tube consists of two or more electrodes in a vacuum inside an airtight envelope. Most tubes have glass envelopes with a glass-to-metal seal based on kovar sealable borosilicate glasses, though ceramic and metal envelopes have been used; the electrodes are attached to leads. Most vacuum tubes have a limited lifetime, due to the filament or heater burning out or other failure modes, so they are made as replaceable units. Tubes were a frequent cause of failure in electronic equipment, consumers were expected to be able to replace tubes themselves. In addition to the base terminals, some tubes had an electrode terminating at a top cap.
The principal reason for doing this was to avoid leakage resistance through the tube base for the high impedance grid input. The bases were made with phenolic insulation which performs poorly as an insulator in humid conditions. Other reasons for using a top cap include improving stability by reducing grid-to-anode capacitance, improved high-frequency performance, keeping a high plate voltage away from lower voltages, accommodating one more electrode than allowed by the base. There was an occasional design that had two top cap connections; the earliest vacuum tubes evolved from incandescent light bulbs, containing a filament sealed in an evacuated glass envelope. When hot, the filament releases electrons into the vacuum, a process called thermio
Ralph H. Baer
Ralph Henry Baer was a German inventor, game developer, engineer. Baer's family had fled Germany just before World War II and Baer served the American war effort, following which he gained an interest in electronics. Through several jobs in the electronics industry, he was working as an engineer at now BAE Systems, when he conceived of the idea of playing games on a television screen around 1966. With support of his employers, he worked through several prototypes until he arrived at a "Brown Box" that became the blueprint for the first home video game console, the Magnavox Odyssey. Baer continued to design several other consoles and computer game units, including contributing to design of the Simon electronic game. Baer continued to work in electronics with over 150 patents to his name. Baer is considered "the Father of Video Games" due to his many contributions to games and the video game industry in the latter half of the 20th century. In February, 2006, he was awarded the National Medal of Technology for "his groundbreaking and pioneering creation and commercialization of interactive video games, which spawned related uses and mega-industries in both the entertainment and education realms".
Baer was born in 1922 to Lotte and Leo Baer, a Jewish family living in Germany, was named Rudolf Heinrich Baer. At age 14, he was expelled from school because of his ancestry and had to go to an all-Jewish school, his father worked in a shoe factory in Pirmasens at the time. Baer's family, fearing increasing persecution, moved from Germany to New York City in 1938 two months prior to Kristallnacht while Baer was a teenager. Baer would become a naturalized United States citizen. In the United States, he was self-taught and worked in a factory for a weekly wage of twelve dollars, he graduated from the National Radio Institute as a radio service technician in 1940. In 1943 he was drafted to fight in World War II and assigned to military intelligence at the United States Army headquarters in London. With his secondary education funded by the G. I. Bill, Baer graduated with a Bachelor of Science degree in Television Engineering from the American Television Institute of Technology in Chicago in 1949. In 1949, Baer went to work as chief engineer for a small electro-medical equipment firm, Inc. where he designed and built surgical cutting machines and low frequency pulse generating muscle-toning equipment.
In 1951, Baer went to work as a senior engineer for Loral Electronics in Bronx, New York, where he designed power line carrier signaling equipment for IBM. From 1952 to 1956, he worked at Transitron, Inc. in New York City as a chief engineer and as vice president. He started his own company before joining defense contractor Sanders Associates in Nashua, New Hampshire in 1956, where he stayed until retiring in 1987. Baer's primary responsibility at Sanders was overseeing about 500 engineers in the development of electronic systems for military applications. However, out of this work came the concept of a home video game console; as he approached retirement, Baer partnered with Bob Pelovitz of Acsiom, LLC, they invented and marketed toy and game ideas from 1983 until Baer's death. Baer was a Life Senior Member of Institute of Electronics Engineers, his son, helped lead the nomination process to elevate him to become an IEEE Life Fellow, the highest level of membership within the organization. Baer married Dena Whinston in 1952.
They had three children during their marriage, at the time of Baer's death, he had four grandchildren. Baer died at his home in Manchester, New Hampshire on December 6, 2014, according to family and friends close to him. Baer is considered to have been the inventor of video games of the concept of the home video game console. In 1966, while an employee at Sanders Associates, Baer started to explore the possibility of playing games on television screens, he first got the idea while working at Loral in 1951, another electronics company, they wanted nothing to do with it at the time. In a 2007 interview, Baer said that he recognized that the price reduction of owning a television set at the time had opened a large potential market for other applications, considering that various military groups had identified ways of using television for their purposes. Upon coming up with the idea of creating a game using the television screen, he wrote a four-page proposal with which he was able to convince one of his supervisors to allow him to proceed.
He was given the time of two other engineers, Bill Harrison and Bill Rusch. They developed the "Brown Box" console video game system, so named because of the brown tape in which they wrapped the units to simulate wood veneer. Baer recounted that in an early meeting with a patent examiner and his attorney to patent one of the prototypes, he had set up the prototype on a television in the examiner's office and "within 15 minutes, every examiner on the floor of that building was in that office wanting to play the game"; the Brown Box was patented on April 17, 1973, given U. S. Patent No. 3728480, became jointly owned by Ralph Baer and BAE Systems. Baer began seeking a buyer for the system, turning to various television manufacturers who did not see interest in the unit. In 1971, it was licensed to Magnavox, after being renamed Magnavox Odyssey, the console was
Stony Brook University
The State University of New York at Stony Brook known as Stony Brook University and SUNY Stony Brook, is a public sea-grant and space-grant research university in Stony Brook, New York. It is one of four university centers of the State University of New York system; the institution was founded 62 years ago in 1957 in Oyster Bay as State University College on Long Island, moved to Stony Brook in 1962. The university has expanded to include 220 major buildings with a combined area of more than 12.2 million gross square feet across 1,454 acres of land. In 2001, Stony Brook was elected to the Association of American Universities, it is a member of the larger Universities Research Association. The university's health science and medical component, collectively referred to as Stony Brook Medicine, includes the Schools of Medicine, Dental Medicine, Health Technology and Management and Pharmaceutical Sciences, Social Welfare, as well as the Hospital, major centers and institutes, programs and community-based healthcare settings, the Long Island State Veterans Home.
Stony Brook University, part of the management team of Brookhaven National Laboratory – a national laboratory of the United States Department of Energy – acquired land for a Research & Development Park adjacent to its main campus in 2004, has four business incubators across the region. The university's impact on the Long Island economy amounts to $7.38 billion in increased output, research expenditures have surpassed the $230 million mark annually. Stony Brook is the largest single-site employer on Long Island. Stony Brook's intercollegiate athletic teams are the Seawolves. Since 1994, they have competed in Division I of the NCAA, are members of the America East Conference and the Colonial Athletic Association; the State University of New York at Stony Brook was established in Oyster Bay in 1957 as the State University College on Long Island, by the governor and state of New York. Established a decade after the creation of New York's public higher education system, the institution was envisioned as a college for the preparation of secondary school teachers.
Leonard K. Olson was appointed as the first dean of the institution and was instrumental in the recruitment of faculty staff and planning of the Stony Brook campus. SUCOLI opened with an inaugural class of 148 students, on the grounds of the William Robertson Coe Planting Fields estate; these first students were admitted on a tuition-free basis. 1961 was a year of firsts as thirty students were conferred degrees in the first commencement and the University was appointed its first president, John Francis Lee. Lee left that year due to political and bureaucratic matters regarding the future of the University and the central administration at Albany. Lee fulfilled his primary task of reshaping the university from a technical science and engineering college of limited degree options to a full-scale university featuring liberal arts programs. In 1960 the Heald Report, commissioned by Governor Nelson Rockefeller, recommended a major new public university be built on Long Island to "stand with the finest in the country", a report that would shape most of the University's growth for years to come.
Ward Melville, a philanthropist and businessman from the Three Village area in western Suffolk County donated over 400 acres of land to the state for the development of a state university and in 1962 the institution relocated to Stony Brook and renamed as the State University of New York at Stony Brook. However, the name has fallen out of favor, since 2005, has been replaced with Stony Brook University; the campus had 782 students enrolled in 1962, but enrollment had increased more than tenfold by 1969, surpassing the 8,000 mark, fueled by the large funding of public higher education in the Sputnik era. In 1963, only three years after the release of the Heald Report, the Governor commissioned the "Education of Health Professions" report; the report outlined the need for expansion of the university system to prepare medical professionals for the future needs of the state. The report was important for Stony Brook as it recommended creation of a Health Science Center and academic hospital at the campus to serve the need of the fastest-growing counties in New York at the time.
In 1965, the State University appointed John S. Toll, a renowned physicist from the University of Maryland as the second president of Stony Brook. In 1966, the University set forth initial timetables for the development of the Health Science Center, which would house the University's health programs and hospital. Despite the budgetary concerns and challenges from Albany, the University released a formalized plan early in 1968 and funding for recruitment of faculty was provided. At the same time, residential housing was expanded to 3,000, the Stony Brook Union opened in 1970, in 1971, the massive expansion project for the campus library was completed. Despite the fast-paced growth, campus infrastructure struggled to keep pace: overcrowding, landscaping and safety were persistent problems at the University, which led to multiple protests and growing tension between the student body and the administration. In January 1968, the infamous “Operation Stony Brook” drug raid resulted in the arrest of twenty nine students and in the fall of 1968, tension climaxed as the administration and students decided on a three-day moratorium to bring together the entire university with the goal of improving communicati
Christopher Strachey
Christopher S. Strachey was a British computer scientist, he was one of the founders of denotational semantics, a pioneer in programming language design. He was a member of the Strachey family, prominent in government, arts and academia. Christopher Strachey was born on 16 November 1916 to Oliver Strachey and Rachel Costelloe in Hampstead, England. Oliver Strachey was the son of Richard Strachey and the great grandson of Sir Henry Strachey, 1st Baronet, his elder sister was the writer Barbara Strachey. In 1919, the family moved to 51 Gordon Square; the Stracheys belonged to the Bloomsbury Group whose members included Virginia Woolf, John Maynard Keynes and Christopher's uncle Lytton Strachey. At 13, Christopher went to Gresham's School, Holt where he showed signs of brilliance but in general performed poorly, he was admitted to Cambridge in 1935 where he continued to neglect his studies. Strachey studied mathematics and transferred to physics. At the end of his third year at Cambridge, Strachey suffered a nervous breakdown related to coming to terms with his homosexuality.
He managed only a "lower second" in the Natural Sciences Tripos. Unable to continue his education, Christopher joined Standard Telephones and Cables as a research physicist, his first job was providing mathematical analysis for the design of electron tubes used in radar. The complexity of the calculations required the use of a differential analyser; this initial experience with a computing machine sparked Strachey's interest and he began to research the topic. An application for a research degree at the University of Cambridge was rejected and Strachey continued to work at STC throughout the Second World War. After the war he fulfilled a long-standing ambition by becoming a schoolmaster at St Edmund's School, teaching mathematics and physics. Three years he was able to move to the more prestigious Harrow School in 1949, where he stayed for three years. In January 1951, a friend introduced him to Mike Woodger of the National Physical Laboratory; the lab had built a reduced version of Alan Turing's Automatic Computing Engine the concept of which dated from 1945: the Pilot ACE.
In his spare time Strachey developed a program for the game of draughts, which he finished in February 1951. The game exhausted the Pilot ACE's memory; the draughts program ran for the first time on 30 July 1951 at NPL. When Strachey heard about the Manchester Mark 1, which had a much bigger memory, he asked his former fellow-student Alan Turing for the manual and transcribed his program into the operation codes of that machine by around October 1951; the program could "play a complete game of Draughts at a reasonable speed". Strachey programmed the first music performed by a computer; that year, short extracts of three pieces were recorded there by a BBC outside broadcasting unit: the National Anthem, "Ba, Ba Black Sheep, "In the Mood". Researchers at the University of Canterbury, Christchurch restored the acetate master disc in 2016 and the results may be heard on Soundcloud. In May 1952, Strachey gave a two-part talk on "the study of control in animals and machines" for the BBC Home Service's "Science Survey" programme.
Strachey worked for the National Research Development Corporation from 1952 to 1959. While working on the St. Lawrence Seaway project, he was able to visit several computer centres in the United States and catalogue their instruction sets, he worked on programming both the Elliott 401 computer and the Ferranti Pegasus computer. Together with Donald B. Gillies, he filed 3 patents in computing design including the design of base registers for program relocation, he worked on the analysis of vibration in aircraft, working with Roger Penrose, developed the concept of time-sharing. In 1959, Strachey left NRDC to become a computer consultant working for NRDC, EMI, Ferranti and other organisations on a number of wide-ranging projects; this work included logical design for computers, providing autocode and the design of high-level programming languages. For a contract to produce the autocode for the Ferranti Orion computer, Strachey hired Peter Landin who became his one assistant for the duration of Strachey's consulting period.
In 1962, while remaining a consultant, he accepted a position at Cambridge University. In 1965, Strachey accepted a position at Oxford University as the first director of the Programming Research Group and the University's first Professor of Computer Science and fellow of Wolfson College, Oxford, he collaborated with Dana Scott. Strachey was elected as a Distinguished Fellow of the British Computer Society in 1971 for his pioneering work in computer science. In 1973, Strachey began to write an essay submitted to the Adams Prize competition, after which they continued work to revising it into book form. Strachey can be seen and heard in the recorded Lighthill debate on AI. Strachey contracted an illness diagnosed as jaundice which, after a period of seeming recovery, returned and he died of infectious hepatitis on 18 May 1975, he developed the Combined Programming Language. His influential set of lecture notes Fundamental Concepts in Programming Languages formalised the distinction between L- and R- values.
Strachey coined the term currying, although he did not invent the underlying concept. He was instrumental in the design of the Ferranti Pegasus computer; the macro language m4 derives much from
Video game genre
A video game genre is a classification assigned to a video game based on its gameplay interaction rather than visual or narrative differences. A video game genre is defined by a set of gameplay challenges and are classified independently of their setting or game-world content, unlike other works of fiction such as films or books. For example, a shooter game is still a shooter game, regardless of when it takes place; as with nearly all varieties of genre classification, the matter of any individual video game's specific genre is open to personal interpretation. Moreover, each individual game may belong to several genres at once; the first attempt to classify different genres of video games was made by Chris Crawford in his book The Art of Computer Game Design in 1984. In this book, Crawford focused on the player's experience and activities required for gameplay. Here, he stated that "the state of computer game design is changing quickly. We would therefore expect the taxonomy presented to become obsolete or inadequate in a short time."
Since among other genres, the platformer and 3D shooter genres, which hardly existed at the time, have gained a lot of popularity. As hardware capabilities have increased, new genres have become possible, with examples being increased memory, the move from 2D to 3D, new peripherals and location. Though genres were just interesting for game studies in the 1980s, the business of video games expanded in the 1990s and both smaller and independent publishers had little chance of surviving; because of this, games settled more into set genres that larger publishers and retailers could use for marketing. Due to "direct and active participation" of the player, video game genres differ from literary and film genres. Though one could state that Space Invaders is a science-fiction video game, such a classification "ignores the differences and similarities which are to be found in the player's experience of the game." In contrast to the visual aesthetics of games, which can vary it is argued that it is interactivity characteristics that are common to all games.
Descriptive names of genres take into account the goals of the game, the protagonist and the perspective offered to the player. For example, a first-person shooter is a game, played from a first-person perspective and involves the practice of shooting; the term "subgenre" may be used to refer to a category within a genre to further specify the genre of the game under discussion. Whereas "shooter game" is a genre name, "first-person shooter" and "third-person shooter" are common subgenres of the shooter genre. Other examples of such prefixes are real-time, turn based, side-scrolling; the target audience, underlying theme or purpose of a game are sometimes used as a genre identifier, such as with "games for girls," games for cats,"Christian game" and "Serious game" respectively. However, because these terms do not indicate anything about the gameplay of a video game, these are not considered genres. Video game genres vary in specificity, with popular video game reviews using genre names varying from "action" to "baseball."
In this practice, basic themes and more fundamental characteristics are used alongside each other. A game may combine aspects of multiple genres in such a way that it becomes hard to classify under existing genres. For example, because Grand Theft Auto III combined shooting and roleplaying in an unusual way, it was hard to classify using existing terms. Since the term Grand Theft Auto clone has been used to describe games mechanically similar to Grand Theft Auto III; the term roguelike has been developed for games that share similarities with Rogue. Elements of the role-playing genre, which focuses on storytelling and character growth, have been implemented in many different genres of video games; this is because the addition of a story and character enhancement to an action, strategy or puzzle video game does not take away from its core gameplay, but adds an incentive other than survival to the experience. According to some analysts, the count of each broad genre in the best selling physical games worldwide is broken down as follows.
The most popular genres are Shooter, Role-playing and Sports, with Platformer and Racing having both declined in the last decade. Puzzle games have declined when measured by sales, however, on mobile, where the majority of games are free-to-play, this genre remains the most popular worldwide. List of video game genres
