A custom font, or character set, is used to create and animate the centipede in the Apple II, Atari 8-bit and Commodore 64 versions of the game. This is a common trick on these systems, used when a game needs a lot of different moving objects. Changing the graphics is as simple as writing new "letters" and "words" to different parts of the screen.

A side effect of this trick is that it's not easy to get a screenshot of a complete centipede!