OpenGL is a cross-platform library for rendering 3D graphics on computer displays, originally developed at Silicon Graphics in the early 1990s . RGL is a library of functions that gives out three dimensional, real-time visualization functionality to the world of R programming. It tries to solve the shortcoming in the current version of R, namely the inability to allow the user to generate interactive 3D graphics. Since 3D images need to be projected on a 2D display, special navigation capabilities are of need to provide insight into 3D relationships. Features such as lighting, alpha blending, texture mapping and fog effects are used to enhance the feature of three-dimensionality. Additional desirable features for interactive data analysis in 3D are the ability to rotate objects, and to zoom in/out so as to examine details of an object, or alternatively, to view it in a different angle. The aim of the project described here is to provide a 3D engine with an API (Application Programming Interface) designed for R. It is implemented as a shared library that uses OpenGL. The syntax of the RGL commands is based on that of the related and familiar standard R commands, thus ensuring that users getting familiar with the standard R can quickly learn the usage of RGL. This paper highlights the capabilities of the RGL library and illustrates them using some examples of statistical applications.