2.7. First Person Shooter (aka FPS)
What light through yonder window breaks? It must be the flash of the double barreled shotgun! We have a long and twisted history with FPS games which started when id Software open sourced code for Doom. The code base has forked and merged numerous times. Other previously closed engines opened up, many engines are playable via emulators, many commercial FPS games were released for Linux and there are quite a number of FPS engines which started life as open source projects. Although you may not be able to play your favorite FPS under Linux (Half-Life plays great under winex) Linux definitely has no deficiency here!
First person shooters are characterized by two things. First, you pretty much blow up everything you see. Second, the action takes place in first person. That is, through the eyes of the character who's doing all the shooting. You may even see your hands or weapon at the bottom of the screen. They can be set in fantasy (Hexen), science fiction (Quake II), present day 'real world' (Soldier Of Fortune) and many other settings.
Like text adventures, FPS fit the engine/datafile format. The engine refers to the actual game itself (Doom, Quake, Heretic2) and plays out the maps and bad guys outlined by the datafile (doom2.wad , pak0.pak , etc). Many FPS games allow people to write their own non-commercial datafile. There are hundreds, even thousands of non-commercial Doom datafiles that you can download for free off the net. Often, companies release their engines to the open source community so we can hack and improve them. However, the original data files are kept proprietary. To this day, you still have to purchase doom.wad .