Flatland: A Romance of Many Dimensions is an satirical novella by the English schoolmaster Edwin Abbott Abbott.

Writing pseudonymously as "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.

Several films have been made from the story, including the feature film Flatland (2007). Other efforts have been short or experimental films, including one narrated by Dudley Moore and the short films Flatland: The Movie (2007) and Flatland 2: Sphereland (2012) starring Martin Sheen and Kristen Bell.

The story describes a two-dimensional world occupied by geometric figures, whereof women are simple line-segments, while men are polygons with various numbers of sides. The narrator is a square named A Square, a member of the caste of gentlemen and professionals, who guides the readers through some of the implications of life in two dimensions.