Backup file format
BUP is a file extension for a backup file format used by a number of programs to create an automatic backup of a data file in case of program errors, or the file becomes corrupt, lost or unusable.
DVD info file (IFO) backup is the most common use for BUP files. Should the drive be unable to read the IFO file, it will attempt to read the data from the BUP file.
BUP is short for “backup.”
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