A positronic brain is a fictional technological device, originally conceived by science fiction writer Isaac Asimov. It functions as a central processing unit for robots, and, in some unspecified way, provides them with a form of consciousness recognizable to humans. When Asimov wrote his first robot stories in 1939 and 1940, the positron was a newly discovered particle, and so the buzz word "positronic" added a scientific connotation to the concept. Asimov's 1942 short story "Runaround" elaborates his fictional Three Laws of Robotics, which are ingrained in the positronic brains of nearly all of his robots. Positronic brains, as such, are a kind of brain made of positrons – small particles which help in the transmission of various thoughts and impulses to the brain and help the brain's cognition relay the selected emotion or solution.