Flatland is a beautiful story about how the Universe would appear from the point of view of 2 dimensional creatures.
The narrator of the story is a square and the world he lives in is called Flatland. All inhabitants of this world are polygons. Low caste beings are irregular and the social status of a being is denoted by the number of sides he has.
For example the square, being 4 sided, is a member of the middle class.
Edwin Abbot, who wrote the story, explores many interesting aspects of how the world would appear from such a perspective. For example, all objects would seem like lines. Though this may seem counter intuitive it is true and can easily be verified by keeping a coin on a table and bringing one's eye down to the level of the table. When the line of sight is exactly along the surface of the table the coin will appear to be a line. In the story he also explores how the world would appear from the point of view of one dimensional creatures (lines) and talks about the Universe from the point of view of a point! This point of course cannot perceive anything else and thinks the entire universe just consists of him and nothing else.
Abbot ends by daring us to dream of dimensions higher than 3. Truly an interesting book...