Fangame
A fangame (also fan game) is an application of parody designed to entertain an audience for generally no profit using the theme of popular culture as an integral aspect of the game components. These games are usually not endorsed -- and sometimes not accepted -- by the company currently in possession of copyrights or trademarks used by this application, and may place their producer in an undesirable situation if these rights are infringed too blatantly.
Fangames can be made using a variety of programs ranging from the text character-based ZZT to powerful programming languages like C++. The majority of fangames are 2D, as 3D is either too difficult or sometimes not possible for some programmers.
Fangames are usually criticized because they use third-party content, rather than original ideas. They also tend to not live up to the games they are derived from.
The "Gray Area"
Because of differing interpretations of copyright law, fangames (and other fan works) are said to be a gray area. Some will argue that they are in violation of copyright, while others state that they count under fair use of parody (see above). This is further complicated by usage of ripped materials. Additionally, some companies actually encourage or otherwise showcase fangames. As a result, most fangamers believe fangames to be legal, as long as the parent company does not complain.
