I Think a lot of pepole don't know opengl, and because of the greate marketing power of microsoft, they have bad information... Opengl is include in the graphic card driver. No need to install anything. A computer who run correctly direc3D, must have a driver and of course opengl with it. And a lot of computer have the graphic card driver install (default by the manufacturer), without directx (or not the lastest one). There is more computer opengl ready than directx, that's a fact. If you don't believe me, explain me how Doom/Quake serie sell well for example :) The only (big) problem is the opengl driver quality on windows. For windows comparing directx and opengl, is like comparing a low level langage, and a high level langage. With opengl you need more work for the same thing. But is you want to make things, out of the line, it's possible. If you want to optimise the 3d engine, you have more room to do it with opengl. With directx you have more nice function which speed up developpement. But this function change from one version to the other. You have to learn again the entire implementation. And if you don't wan't to make dirty programmation, you have to rebuild your graphic engine, to adapt it to the new version. Why directx is more use in game developpement? Because money makes game developpement rules. Directx is for the short term. Opengl is for the long term. Nowadays money choose short term investement :) Noone talk about the political part of this choice. If you choose directx, you choose to support a one private companie technologie. Microsoft, who want to put a pc in every room of your life ( Microsoft use the console market to achieve this). If microsoft technologie is used by every one, this companie will gain a great power. They will decide how the game developpement will be in the futur. Do you want to give them, such power? Opengl is more, "make something good for everyone". It's about sharing technologie, and making a rock solid API, even if this takes time. PS: I like both directx, and opengl for different reason. I think microsoft with the xbox, make the best plateform for console developpement. But for my mac/pc developpement, opengl is the king.