A MemoryBlock gives our BrainBlock extra memory. The MemoryBlock uses an SD Card.
This lets us do things such as:
SD Cards are made of a special kind of memory called Flash Memory. Flash memory is special because it can remember information even when the power is turned off.
Flash memory uses Floating Gate Transistors to store information. They are sort of like balloons that you can store a static charge on; but an SD card has millions or billions of tiny static charges that are carefully protected and can last many years with the power off.