Memory Slots...How do they Work?

Okay, I know some machines have memory slots and some don't. But I have absolutely no idea how they are used/work. I have never seen them used, and never have seen any information on how to use them. Are they even intended for use in the US? I'm mostly just curious.

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Sean Paul
CP 'Screw Crew 2003

This could be a little wrong but I think I have the idea...first off you need a memory card with Japanese DDR data on it...next can either just have edits on it or just have it to save stuff(i.e. like playing at home...if you AA or AAA a song at the arcade insted of you house it will save.) and to get into the step edits I think you have to go to the song and hit the Right or left arrow twice. I hope that helps....

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