LinuxDig.com : Linux Dictionary Term Mesa

1. A free implementation of the OpenGL API, designed and written by Brian Paul, with contributions from many others. Its performance is competitive, and while it is not officially certified, it is an almost fully compliant OpenGL implementation conforming to the ARB specifications. From Linux Guide @FirstLinux

Source:
Linux Dictionary (version 0.12)
author: Binh Nguyen
linuxfilesystem(at)yahoo(dot)com(dot)au

This Linux Dictionary is distributed under the GNU
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2. An implementation of the OpenGL (Open Graphics Library) API (Application Programming Interface). It provides standard guidelines and a toolset for writing 2D and 3D hardware-assisted graphics software. From I-gloss

3. Mesa is a free implementation of the OpenGL API, designed and written by Brian Paul, with contributions from many others. Its performance is competitive, and while it is not officially certified, it is an almost fully compliant OpenGL implementation conforming to the ARB specifications - more complete than some commercial products out, actually. From 3DFX HOWTO