Conway's Game of Life is played on an infinite two-dimensional board.   The state of a cell is either alive or dead.   The world can be initialized in any way, but from the initial generation, the world continues one generation at a time, each generation dependent only on the previous generation.   In fact, the state of a cell in generation g + 1 depends only on the state of the 9 cells around that cell in generation g.   If a cell is alive in generation g, and it has 2 or 3 living neighbors, or if it is dead, and it has exactly 3 living neighbors, it will be alive in generation g + 1, otherwise it will be dead.   This game was invented by John Horton Conway in 1970.

In July of 2007 I looked into creating animated GIFs and below are the results.  Here you can see some common Game of Life constellations:  block, blinker, tub, beehive, loaf, glider, boat, long boat, ship, pond, canoe, and pulsar.

Here is a life world you can play with.  First click the center of the X for calibration purposes, then click the buttons below or use the keyboard shortcuts indicated on the buttons.  To change the state of a cell, click on it.