I mean the ones like The Legend of Zelda that saved your game without the use of passwords. How was your game saved on the cartridge? Did it work the same way as an old floppy disk?
There was a battery that powered a chip that kept the save game in memory.
If the battery fails (which is a likely result for those cartridges now) then the cartridge loses the functionality of saving the game, but everything else still works normally.
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