: It could be part of a "Repack" for a large game, where "RP3" might stand for a specific title (like Red Dead Redemption or Rayman Origins ). How to use it

: Right-click on Part 1 only and select "Extract Here."

: The software will automatically pull data from the other parts to create the full, uncompressed file.

Because this is part of a split archive (indicated by .part1 ), you generally cannot open it successfully without having all the other parts (e.g., .part2.rar , .part3.rar ) in the same folder. What is this file likely for?

: Many users share PlayStation 3 game files split into parts to bypass upload limits on hosting sites.