Mesa is a 3-D graphics library with an API which is very similar to that of OpenGL.*

Mesa is a 3-D graphics library with an API which is very similar to
that of OpenGL.* To the extent that Mesa utilizes the OpenGL command
syntax or state machine, it is being used with authorization from
Silicon Graphics, Inc.(SGI). However, the author does not possess an
OpenGL license from SGI, and makes no claim that Mesa is in any way a
compatible replacement for OpenGL or associated with SGI. Those who
want a licensed implementation of OpenGL should contact a licensed
vendor.

Please do not refer to the library as MesaGL (for legal reasons). It's
just Mesa or The Mesa 3-D graphics library.

* OpenGL is a trademark of Silicon Graphics Incorporated.