Elementary Cellular AutomataA row of cells, each black or white. To make the next row, every cell looks at just itself and its two neighbours and follows one fixed lookup rule. That is the whole machine — yet rule 30 spits out noise good enough for a random-number generator, and rule 110 can run any computer program.In the 1980s Stephen Wolfram catalogued all 256 of these rules and sorted their behaviour into four classes: freeze, repeat, fractal, and chaos. Rule 110 was later proved Turing-complete, meaning the simplest imaginable rule is already as powerful as computation gets.