Analog robot
An analog robot is a type of robot which uses analog circuitry to go toward a simple goal such as finding more light or responding to sound. The first real analog robot was invented in the 1940s by William Grey Walter. The name of these robots were ELSIE and ELMER (Electro Mechanical Robot). The original circuitry was developed using two vacuum tubes and a photocell to search and follow a light. Recently a kind of analog robots was developed by Mark Tilden.
Robots in literature
The first use of the word "Robot" was in Karel Čapek's play "R.U.R. (Rossum's Universal Robots)" written in 1920 and first performed in Czechoslovakia in 1921, in New York City in 1922 and an English edition published in 1923. Artificial living beings are created from a chemical substitute for protoplasm but over time they learn about violence from their human creators and begin to revolt. The play ends on an optimistic, even spiritual, note as the artificial biology leads a male and female robot to fall in love and inherit the earth.