Recreational computer programs. Computers have been used to play games from the very start, and as the computers have become more powerful and cheaper, the games have become more sophisticated, particularly in their appearance and sound. Much computer game playing is done on purpose-made computers called games consoles
. Typically, games are controlled using a joystick
or similar hand-held device. They are available on a variety of data media and can also be downloaded from the Internet
. The serious side of games is in the algorithms underlying them, many of which have become important in other areas of computing. Equally, games have inherited techniques from industrial and military simulators. Currently virtual reality
is becoming more important in games, while networks have made the multiuser game popular. See also computer chess
One of the founders of computer science and a leading scientist of Bell Laboratories, Claude Shannon (1916–2001), estimated the number of possible computer games as 10120. How big is this number? In comparison, there are thought to be 1075 atoms in the entire universe.