OpenGL isn t a library It s a language the Open Graphics Language It started out as a set of tokens that could be passed from graphics clients to graphics servers a token stream The library that everyone s used to using conceptually just generates those tokens in the stream for you OpenGL is certainly not a specification the OpenGL Specification is a specification but OpenGL is a language or if you re not convinced of that a technology The really irritating thing about this is that it used to be on the SGI web site but I can t find the page anymore