While the Saturn did have internal storage (albeit powered by a watch battery), it wasn't a lot, which meant this became a necessity. However, it was pretty glitchy and unreliable. Every now and then what looked like a line of corrupted code would appear in the memory, and if you deleted it it erased EVERYTHING on the cartridge. Needless to say, it's unfortunate that such a temperamental thing was a vital purchase.
Backup Memory Cartridge
Alborke Seagoonadded October 15, 2017