The Atari 16K Memory Module

        Installing additional memory into the Atari 800 couldn't have been any easier.   Simply open the cartridge door (which automatically powered off the system for safety to both the user and the system), turn the plastic handles (later 800's had screws with washers) and lift off the top cover of the Atari 800.   Now you had access for 4 expansion slots.   Slot #0 was for the Operating System ROM board, Slots #1 to #3 were for memory modules.   (Slot #3 was also used for 80 column video cards).   Simply insert the memory module into the next free slot and place the cover back onto the case, secure the latches or screws, close the cartridge door and you were all set, no configuration software to run, no jumpers to set.    Looks more like Atari invented "Plug N Play" then Microsoft :)