Abstract: A system made up of a portable information terminal mountable on a shopping cart for providing product and advertising information while the cart is moved inside a store and an external memory device connectable to the portable information terminal, the external memory device including a memory housing, a non-volatile memory storing data in the memory housing, and a first electrical connector projecting from the housing for allowing a processor to access the stored data; the portable terminal including a terminal housing including a display, a processor in the terminal housing for causing the display to display product information and advertisements, and a second electrical connector inside the housing complementary to the first electrical connector for connecting an external memory device to the processor, the terminal housing including a passage providing access to the second electrical connector from outside the terminal housing and at least one door recessed in the passage shiftable from a first position