written by Isaac Asimov
published in 1958
A short story
Also a title in the Susan Calvin series.
Set in the Foundation universe
U.S. Robots is planning the production of the LNE series of robots, which are designed for boron mining in the asteroid belt. After a technician neglects to lock a terminal, a factory tourist accidentally reprograms the prototype LNE, wiping clean the structure of the robot's brain, and rendering it a baby in all effects.
Robopsychologist Susan Calvin experiments with it, in the process naming it "Lenny" (and developing maternal feelings for it), and after a month, has been able to teach it a few simple words and actions. She gets emotionally attached to Lenny and realizes that robots can be built that are able to learn, instead of being built for a fixed and specific purpose.
Complications arise when Lenny, unaware of its own force, breaks the arm of a computing technician, which is about to cause widespread "robots attacking humans" panic. However, Susan Calvin manages to exploit the sense of danger to add a new thrill of robotic investigation, just as happens with space exploration or radiation physics.