- Any live cell with 0 or 1 live neighbors becomes dead, because of underpopulation
- Any live cell with 2 or 3 live neighbors stays alive, because its neighborhood is just right
- Any live cell with more than 3 live neighbors becomes dead, because of overpopulation
- Any dead cell with exactly 3 live neighbors becomes alive, by reproduction
Programming Projects for Advanced Beginners #2: Game of Life