Electronic Arts - http://www.ea.com

 

id Software - http://www.idsoftware.com

 
  Experience mind-blowing adrenaline rushes at EA SPORTS BIG, The most realistic, in-your-face sports action at EA SPORTS, all the fantasy, sci-fi and simulations you can play at EA GAMES and more.   Home of the world class games creators of such titles as: the "Doom" series, the "Quake" games, and most recently the smash hit "Return to Castle Wolfenstein".  
 
 
 
 

Atari - http://www.atari.com

 

Sierra Entertainment - http://www.sierra.com

 
  Once a big name in the home game console market and now a major player in PC software, Atari looks like it'll be here for many years to come.   A well established software producer, being involved with the PC gaming world for many years. Producer of such modern classics as "No One Lives Forever 2" and "HomeWorld 2".  
 
 
 
 

Origin - http://www.origin.ea.com

 

Eidos - http://www.eidos.com

 
  Now on off-shoot of Electronic Arts, Origin has always been famous for creating highly detailed and imersive entertainment software, such as the "Ultima" and "Wing Commander" game series.   Probably most famous for the world of "Tomb Raider" and "Lara Croft", Eidos have produced a large number of high quality game classics.  
 
 
 
 

Activision - http://www.activision.com

 

Microsoft Games - http://www.microsoft.com/games

 
  Another of the old classic entertainment software producers for the PC, Activision is still producing games software today.   Once dismissed by the gaming community, Microsoft has become a major plays thanks in part to their XBOX games console and the new range of excellent PC Games.  
 
 
 
 

Nintendo - http://www.nintendo.com

 

Sony - http://www.sony.com

 
  Home of the Nintendo GameCube as well as a whole family of old games consoles. One of the "Big Three" games console manufacturers.   With their Playstation games consoles, Sony is one of the world most successful console manufacturers. Also famous for their selection of on-line games, many of which are considered to be among the best.