In 1970 John Conway set out the simplest universe he could imagine: a grid of cells, each just alive or dead, obeying four little rules about their neighbours. No randomness, no plan. Out of it crawl gliders, pulsing oscillators, even machines that build other machines. It is the purest proof that complexity needs no designer.
Every cell looks only at its eight touching neighbours and obeys these, all at once, each tick:
Draw some cells, hover to see each one's fate, then step the clock.
Some shapes are perfectly content: a block just sits there forever, a still life. Others are restless but trapped in a loop — oscillators that breathe between two or three shapes, over and over.
Load a few and watch them tick.
Here's the moment Life feels alive. Five cells in the right arrangement don't sit and don't merely flicker — they crawl. Every four ticks the glider reappears one step down and across, walking forever in a straight diagonal.
Launch a few and watch them travel.
Decades of hunting have turned up a whole bestiary: spaceships that fly, and the famous glider gun — a contraption that endlessly manufactures gliders and fires them off across the grid. Living things, building living things.
Pick a creature and click the board to place it. Try aiming a gun's stream into something.
A clean grid, and your hand. Draw a tangle of cells, set the clock running, and watch what your scribble decides to become — most things flare and die, a few settle into still lifes and blinkers, and now and then a glider escapes and sails away. The same four rules every time.