If you download a complete global "datset" for a game like Resident Evil , you might end up with 15 different files representing the exact same core game. It uses a parent-clone relationship hierarchy to select exactly one optimal version of a game based on your personal geographic and language preferences, discarding the redundant duplicates. The Benefits of a PS1 1G1R Redump Set
This script tells igir to read the DAT, pull from your full set, and output only one version per game (priority USA), organizing multi-disc games into folders.
(“one game, one redump”) is a convention used by some preservation communities to indicate a single, verified redump of a disc image for a particular Sony PlayStation release. “Redump” refers to creating a bit-for-bit archival copy of optical media (in this case, PlayStation CD-ROMs) intended for preservation and verification against known-good dumps.