Topic summary
Controller Pak
Extracted from the Wikipedia article Nintendo 64 accessories.
Controller Pak
The Controller Pak (NUS-004) is the console's memory card, comparable to those of the PlayStation and GameCube. Compatible games can save player data to the Controller Pak, which plugs into the bottom of the Nintendo 64 controller, as do the Rumble Pak and Transfer Pak. The Controller Pak was marketed for exchanging data between Nintendo 64 owners, because data on the game cartridge cannot be transferred.