From Wikipedia, the free encyclopedia

Within contemporary
geometry there are many kinds of geometry that are quite different from
Euclidean geometry, first encountered in the forms of
elementary geometry,
plane geometry of triangles and circles, and
solid geometry. The conventional meaning of *Non-Euclidean geometry* is the one set in the nineteenth century: the fields of
elliptic geometry and
hyperbolic geometry created by dropping the
parallel postulate. These are very special types of
Riemannian geometry, of
constant positive curvature and
constant negative curvature respectively.

## Subcategories

This category has the following 3 subcategories, out of 3 total.

## Pages in category "Non-Euclidean geometry"

The following 12 pages are in this category, out of 12 total.
This list may not reflect recent changes.