Pan Functionality using OpenGL 2.0


This is my first post in this forum and to start with this I would like to know how panning to be done in OpenGL. I referred some discussions went through from the link ( Since I am new to OpenGL concepts and I had done zoom functionality of my 3D model using Camera functions like setPos and setDir. I would like to know is there any same way to do Pan like this or Is there any API available in OpenGL Matrix to get started.