The Memory Banks is a location in Bowser's body, as seen in Mario & Luigi: Bowser's Inside Story. It is in Bowser's brain and is responsible for storing all of Bowser's memories. The Memory Banks are personified as an organized computer database in the form of a library, with each memory stored as a separate file on shelves and is analogous to memory stored on a computer's hard disk. It is maintained by Bowser Memory Neuron who backs up, manages and protects the memories from intruders.
When Bowser cannot recall the combination to a safe that contains a Star Cure in Bowser's Castle, he tells Starlow to help out, although she refuses until he asks politely. When Starlow, Mario and Luigi go to the Memory Banks, they encounter the sphere, which scans them and deems them to be "viruses". It then turns into the Bowser Memory ML, digital copies of the Mario bros., and attacks.
After defeating bowser memory MLEdit
After being defeated, the Memory ML decides to cooperate and changes into Bowser Memory P, based on Peach, claiming that the form is based on Bowser's most carefully preserved memory and is meant to aid in communicating with the Mario Bros. It states that the memory containing the combination to the safe was damaged after Bowser was smashed against a boulder by the Fawful Express. Retrieving the scrambled memory from the archives, the brothers work to repair the memory and restore the combination by doing a jigsaw puzzle. The combination turns out 989888241983. Bowser is then able to open the safe and grab the Star Cure! (yey)