Square World

A square world is a type of world. they are square shaped (though not as tall as it is long or wide) worlds who have around atmosphere (like a planet). The main difference is (besides the shape) that inhabitants can literally walk off the world. They rotate on their own and around their solar system's sun, but the gravity's central point is at the dead bottom, and if one managed to go past that boundary then he or she will fall through the atmosphere, therefore die a burning death. And even if she or he DID get past it, the lack of oxygen will become a problem for most.

Even though that the top is more like plains (where in that case you would get sunlight forever), square worlds still have a day and night cycle. Square worlds are slightly tilted (when viewing from space), and this rotation allows for a day and night cycle, through the night will be nearly only 1 out 4 as long as the day.