A game is structured playing, usually undertaken for enjoyment and sometimes used as an educational tool. Games are distinct from work, which is usually carried out for remuneration, and from art, which is more often an expression of aesthetic or ideological elements.
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Old age
Old age consists of ages nearing or surpassing the average life span of human beings, and thus the end of the human life cycle. Euphemisms and terms for old people include seniors (American usage), senior citizens (British and American usage) and the elderly. Old people have limited regenerative abilities and are more prone to disease, syndromes, and sickness than younger adults. For the biology of ageing, see senescence.
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Usability
Usability is the ease of use and learnability of a human-made object. The object of use can be a software application, website, book, tool, machine, process, or anything a human interacts with. A usability study may be conducted as a primary job function by a usability analyst or as a secondary job function by designers, technical writers, marketing personnel, and others.
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User interface
The user interface, in the industrial design field of human¿machine interaction, is the space where interaction between humans and machines occurs. The goal of interaction between a human and a machine at the user interface is effective operation and control of the machine, and feedback from the machine which aids the operator in making operational decisions.
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Video game
A video game is an electronic game that involves human interaction with a user interface to generate visual feedback on a video device. The word video in video game traditionally referred to a raster display device, but following popularization of the term "video game", it now implies any type of display device. The electronic systems used to play video games are known as platforms; examples of these are personal computers and video game consoles.
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