A long extension, sometimes also called a "wing", hanging off
from the main body of a spaceship or puffer perpendicular to the
direction of travel. For example, here is a sparking c/3 spaceship
which contains two arms.
Many known spaceships have multiple arms, usually fairly narrow.
This is an artefact of the search methods used to find such
spaceships, rather than an indication of what a "typical" spaceship
might look like.
The Game of Life is not your typical computer game. It is a cellular
automaton, and was invented by Cambridge mathematician John Conway.
This game became widely known when it was mentioned in an article
published by Scientific American in 1970. It consists of a grid of
cells which, based on a few mathematical rules, can live, die or
multiply. Depending on the initial conditions, the cells form various
patterns throughout the course of the game.
Rules
For a space that is populated:
Examples
Each cell with one or no neighbors dies, as if by solitude.
Each cell with four or more neighbors dies, as if by
overpopulation.