<P> Newzoo reports that the PC gaming sector is the third largest (and estimated in decline), with the consoles second largest, and mobile, even smartphone gaming sector alone biggest, and across all platforms as of 2016, 2.2 billion gamers generate US $101.1 billion in revenue (i.e. all numbers exclude hardware costs), and "Digital game revenues will account for $94.4 billion or 87% of the global market . Mobile is the most lucrative segment, with smartphone and tablet gaming growing 19% year on year to $46.1 billion, claiming 42% of the market . In 2020, mobile gaming will represent just more than half of the total games market...China expected to generate $27.5 billion, or one - quarter of all revenues in 2017 ." PC is considered synonymous (by them and others) with IBM PC compatible systems; while mobile computers--smartphones and tablets, such as those running Android or iOS--are also personal computers in the general sense . The "APAC" region is estimated to generate $46.6 billion in 2016, or 47% of total global game revenues (note, not only "PC" games). China alone accounts for half of APAC's revenues, reaching $24.4 billion, cementing its place as the largest games market in the world, ahead of the US's anticipated market size of $23.5 billion . China is expected to have 53% of revenues from mobile in 2017 (46% in 2016). </P> <P> The uncoordinated nature of the PC game market and its lack of physical media make precisely assessing its size difficult . </P> <P> Although personal computers only became popular with the development of the microprocessor and microcomputer, computer gaming on mainframes and minicomputers had previously already existed . OXO, an adaptation of tic - tac - toe for the EDSAC, debuted in 1952 . Another pioneer computer game was developed in 1961, when MIT students Martin Graetz and Alan Kotok, with MIT student Steve Russell, developed Spacewar! on a PDP - 1 mainframe computer used for statistical calculations . </P> <P> The first generation of computer games were often text adventures or interactive fiction, in which the player communicated with the computer by entering commands through a keyboard . An early text - adventure, Adventure, was developed for the PDP - 11 minicomputer by Will Crowther in 1976, and expanded by Don Woods in 1977 . By the 1980s, personal computers had become powerful enough to run games like Adventure, but by this time, graphics were beginning to become an important factor in games . Later games combined textual commands with basic graphics, as seen in the SSI Gold Box games such as Pool of Radiance, or Bard's Tale for example . </P>

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