Why eight yes/no answers can draw a fractal, make noise or compute: elementary cellular automata
30seconds
Take a row of lit and dark squares and repeat one tiny rule to make the next row: look at a square and its two neighbours, then decide if it is lit. There are only 256 such rules, yet Rule 90 draws a perfect fractal, Rule 30 makes noise good enough to generate random numbers, and Rule 110 is proven able to run any program.
Flip the eight answers of the rule yourself, tap the top row to seed it, and watch order, chaos and computation appear from almost nothing.
Deep dive · 3 min
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