This document provides a brief and incomplete introduction to the work of Alan Turing. It discusses ideas from set theory by Cantor and Russell. It mentions Turing's proof that there is no general algorithm to determine if a computing machine will halt on all inputs. The document notes Turing conceived of a universal computing machine that could simulate any other machine by reading its configuration from an infinite tape, and highlights the coincidence that the same logical principles apply to both mathematical problem solving and department store operations.