Flatland: A Romance of Many Dimensions is a satirical novella by the English schoolmaster Edwin Abbott Abbott, first published in 1884 by Seeley & Co. of London. Written pseudonymously by “A Square”, the book used the fictional two-dimensional world of Flatland to comment on the hierarchy of Victorian culture, but the novella’s more enduring contribution is its examination of dimensions of space.
How can a being living in a world of 2 dimensions of space understand what (and where) would be the 3rd dimension? The way we would not understand how a thief living in 4 dimentional space would manage to steal the safe from our bank would be similar to beings living in 2 dimentional not being able to understand how we, 3-dimentional beings, could steal a safe from their 2-dimentional bank. For us would be very easy; simply lifting it from above! But for such beings, living in 2 dimentions, this would not be possible to understand!
You can download or read online this very interesting book from project gutengerg ( here ).