Unlike CD-RW discs that always remain open with UDF format with packet writing soft-ware, CD-R discs can be finalized to ISO format. Discs that are finalized to ISO can be read by any Windows computer. No UDF reader software is needed.
Discs that are not finalized remain UDF discs and require UDF reader software. Windows 2000 includes UDF reader capability. A CD-R disc that has been finalized can be made writable again by formatting it as described above.