This article explains the different formats that use the UDF file extension. It also explains how to open each type, and how to save each format to a format with a different file extension, such as ISO, MP4, AVI, or CSV.
How do I open a UDF file?
A file with the UDF file extension is most likely a Universal Disk Format file or an Excel User-Defined Function file.
UDF is a common file system used by optical media burning applications to store files on discs, so the actual UDF file extension (.UDF) may not be all that common. Instead, even though the program doing the burning is doing so using the UDF standard, it is most likely associating the file with itself by appending a different file extension to the end of the filename.
Some UDF files may instead be Excel User Defined Functions created by Microsoft Excel that perform certain predefined functions when opened. Others may be Ricoh Address Books that contain user information.
