Manhunt 2 uncut is still available for those looking. Well to answer that, you need to know what is ROM image or ROM file.
The main use of ROM is to store firmware, now you may be wondering “and what is firmware?” Let me answer you - firmware is kind of software that closely related to a specific hardware and needs updates frequently, that was the firmware short explanation now back to ROM again, as I said that the main use of it is to store firmware or application software in something called plug-in cartridges.