they are often confused to newbie. I am newibe. I think loader is :load some file format to opengl or d3d supported data type. exporter is :export data in some 3d software to file ,it seem to save as .... it often use api to export. because it need access 3d software self data in memory. converter is :just a file to file tool. it do not any api ,need you know each file format that how to store data. right? give me some supplement. thanks.