I'm sure we've all played plenty of games that have the ability to save progress. There are lots of different ways that can work. There's passwords and cart based battery powered saves, common among the classic games. Some systems, like PlayStation, have special memory cards that are unique to the system. Other systems, mainly those in the current generation, have built in hard drives like a computer. The Wii can also use SD cards, which are commonly used by digital cameras to store photos as files.
What approach do you think is the best for storing saves?