Hello everyone I have been looking into using openGL and windows platform

I understand that windows includes gl.h and glu.h along with there SDK and that those headers support openGL 1.1 functions, but in order to use the newer functions of openGL
I must using the headers glext.h, glxext.h, and wglext.h.

Now if I use these, what are the limitations on using them? What are the licenses on them? Can I create and sell a commercial product such as a game or modeling software?
Or will I have to distribute the source or something along those lines?