on the screen as a new line directly below the previous generation's line,
leading the screen to scroll vertically.
-The rules which govern the time evolution of this system depend only on the
-current state of a given cell and the state of its two immediate neighbors.
-These rules are formalized as
+Since these are "elementary" cellular automata, the rules which govern the time
+evolution of this system depend only on the current state of a given cell and
+the state of its two immediate neighbors. These rules are formalized as
[Wolfram codes](https://en.wikipedia.org/wiki/Wolfram_code),
where the code number is directly convertible into a rule set.