The GRToolbox is a set of programs that allow the user to execute operations on polygons or point sets. Often requested operations such as rotating, clipping and sorting are already implemented in the toolbox. More specific ones can easily be added. One of the most powerful features of the GRToolbox is the possibility to combine the small tools to execute complex operations on the point data. Both, extendibilety and combination of programs is a result from the module structure of the toolbox. Every tool is a separate program. But all programs share most of the code. This garants that all programs are handled in the same way, which makes programming and learning how to use the tools easy.