The basic operation of OpenGL's graphical pipeline is to accept vertex data (points, lines, triangles, and polygons) and pixel data (graphical image data), convert them into fragments and store them in the frame buffer. The frame buffer serves as a major interface between developers and the computer display, which maps each frame of graphic contents into memory space for read-write operation. OSG encapsulates the whole OpenGL vertex transformation and primitive assembly operations in order to manage and send vertex data to the OpenGL pipeline, as well as some data transmission optimizations and additional polygonal techniques for improving rendering performance.