Puzzles
In a two-rule grid game, find a pattern that walks across the board forever
Conway's Game of Life runs on just two rules about which cells live or die based on their neighbours, applied to a grid, generation after generation. Most starting patterns fizzle out or freeze in place. Can you find a small pattern that repeats its own shape every few steps while drifting steadily across the board?
Reveal the answer
The glider — five cells that reproduce their own shape, shifted diagonally by one cell, every four generations. Richard K. Guy found it in 1970 while John Conway's group at Cambridge was tracking other patterns; Conway has said the credit belongs to Guy, not him. It later became an unofficial symbol of hacker culture online.