A free implementation of the OpenGL API -- runtime 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. However, the author makes no claim that Mesa is in any way a compatible replacement for OpenGL or associated with Silicon Graphics, Inc. This library provides a pure software rasteriser; it does not provide a direct rendering-capable library, or one which uses GLX. For that, please see libgl1-mesa-glx. On Linux, this library is also known as libGL or libGL.so.1.