A method of writing data into identification media of various types (IM-X, IM-Y) via assigned write/read stations WR in accordance with an embodiment of the present application includes a step wherein, a virtual, identification media-independent reference file system RFS is defined. All access keys RKi are replaced by a file system key FSK and all access rights ACi of subsections Bi are suspended and a file system FS, corresponding to the reference file system RFS, is initialized or written into the identification media: (FS(IM-X), FS(IM-Y)). In doing so, a file system starting point (FS-S(IM-X), FS-S(IM-Y)) is defined in the identification media (IM(FS) and in the assigned read/write stations WR(RFS) so that applications (App(RFS) corresponding to the virtual reference file system RFS can be written into the identification media and executed. The method allows for the writing into or execution of generally defined applications (App(RFS) into initialized identification media of various types (IM-X(FS), IM-Y(FS)) without adapting them.