If you are exploring a specific "300 ROM" pack or report, it likely covers these standard technical variations: File Formats
It’s smaller than full 1G1R (1 Game 1 ROM) sets (~500+ unique titles) but larger than a “best 50” list. Nintendo 64 N64 - 300 ROMs - SoushkinBoudera
When dealing with N64 ROM collections, you will likely encounter different file extensions. These reflect how the data was originally "dumped" from the cartridge: Reddithttps://www.reddit.com If you are exploring a specific "300 ROM"
However, the collection remains a cult classic for three reasons: Nintendo 64 N64 - 300 ROMs - SoushkinBoudera
This collection is a good starting point for your retro gaming journey.