what are mesa and mesaaux ???

i am new to the openGL world. I am using a Solaris. A sample program I saw uses aux*() for window handling and mouse interfacing etc. The book I'm reading uses GLUT. I'm totally confused ? What's this aux ??? Is it Mesaaux ? Me totally confused. Please help !!!

[spak]

Here's a fast explanation

mesa ==> OpenGL like API( exactly the same except that it doesn't have OpenGL's endorsement)
more info at http://www.mesa.org

GLUT ==> windowing manager that sits on top of native windowsing system(X window, Windows , etc )