## ::Plane (geometry)

### ::concepts

Plane::mathbf    Point::geometry    Vector::planes    Space::equation    Parallel::vmatrix    Complex::points

Two intersecting planes in three-dimensional space

In mathematics, a plane is a flat, two-dimensional surface. A plane is the two-dimensional analogue of a point (zero dimensions), a line (one dimension) and three-dimensional space. Planes can arise as subspaces of some higher-dimensional space, as with the walls of a room, or they may enjoy an independent existence in their own right, as in the setting of Euclidean geometry.

When working exclusively in two-dimensional Euclidean space, the definite article is used, so, the plane refers to the whole space. Many fundamental tasks in mathematics, geometry, trigonometry, graph theory and graphing are performed in a two-dimensional space, or in other words, in the plane.

Plane (geometry) sections
Intro  Euclidean geometry  Planes embedded in 3-dimensional Euclidean space  Planes in various areas of mathematics   Topological and differential geometric notions   See also  Notes  References  External links

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