Just what is it? Is it downloadable? Where can I download it? Thanks

OpenGL is a graphics library like Direct3D and DirectDraw (OpenGL can also handle 2d, not only 3d).
It''s included in windows. The header files you need for it come with MSVC++. If you use another compiler I guess you can download the header files (and everything else that is missing) from OpenGL.org

A big plus of OpenGL is that it is system independant. You can run it on Win98, WinNT, Linux, Sun, whatever system you want. Just give it a rendering context (that procedure varies from system to system) and it will render whatever you tell it to render.
It works like a state machine. Think of it as a bunch of states that influence the rendering process and some functions to actually render something. This simple structure allows you to do pretty much with very little efford. I never really worked with Direct3D so I can''t compare the dificulty level, but people say that OpenGL is easier to learn.
Someone once said that OpenGL is like a comfortable Mercedes and Direct3D is more like a fast Porsche or something like that. When you get it to work, Direct3D rocks. But you''ll get faster results (in astonishing quality, in my oppinion) with OpenGL.
Don''t quote me on this. I''m just reffering to someone else here. I don''t even know his name, I just remember this phrase rughly.

I used this comparison to Direct3D because OpenGL is very similar to Direct3D. It has a completely different syntax and structure, but it does the same job and gives you similar results.

Hope that helped.

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