M-4
See M-4 multitronic unit for the failed computer unit by this same name.
M-4 was the designation for a robot constructed by Flint. It served as his ", housekeeper, gardener, and guardian."  The robot hovered in the air and was capable of firing a type of heat beam. 

It was destroyed in 2269 and immediately replaced by a second unit: "Too useful a device to be without, really". ()

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Artificial lifeforms