- Type A— Glider Guns and Spaceship Guns
Oscillating objects which emit moving objects at a constant rate.
- Type B— Puffer Spaceships
Moving objects leave behind objects at a constant rate.
- Type C— Growing Spaceships
Moving objects in which the front and back move at different rates,
resulting in an object which expands in the middle at a constant rate.
- Type D— Expanding Objects
Objects in which moving parts leave behind a connected trail ending in
a stable or oscillating end (wickstretchers) or in which the boundaries move enclosing
a continuosly growring stable or oscillating pattern (spacefiller).
- Type E— Others
Infinite objects which do not fit the above categories