Sony's Playstation 3 is fully backwards compatible with Playstation 2 and Playstation One games. However, unlike the PS2, the PS3 does not have any memory card slots. Therefore, to transfer your saves onto your PS3 console from your PS2, the memory card reader is required. Plug the memory card reader into one of the available USB slots on the PS3, then put your memory card into the reader and transfer the saves from there.