The wikipedia article explains it better than i could,It is basically a simulation of life.
Any live cell with fewer than two live neighbours dies, as if caused by under-population.
Any live cell with two or three live neighbours lives on to the next generation.
Any live cell with more than three live neighbours dies, as if by over-population.
Any dead cell with exactly three live neighbours becomes a live cell, as if by reproduction.
so you can try to create patterns that will live for as long as possible.
It's not really a game.
Clear the grid and then choose "line of ten" then run simulation and you will see what i mean.
Panda probalby didn't like the fact it was an exe.