
In
mathematics, a plane is a
Euclidean (
flat), two-
dimension
In physics and mathematics, the dimension of a mathematical space (or object) is informally defined as the minimum number of coordinates needed to specify any point within it. Thus, a line has a dimension of one (1D) because only one coor ...
al
surface that extends indefinitely. A plane is the two-dimensional analogue of a
point (zero dimensions), a
line
Line most often refers to:
* Line (geometry), object with zero thickness and curvature that stretches to infinity
* Telephone line, a single-user circuit on a telephone communication system
Line, lines, The Line, or LINE may also refer to:
Art ...
(one dimension) and
three-dimensional space. Planes can arise as
subspaces of some higher-dimensional space, as with one of a room's walls, infinitely extended, or they may enjoy an independent existence in their own right, as in the setting of two-dimensional
Euclidean geometry
Euclidean geometry is a mathematical system attributed to ancient Greek mathematician Euclid, which he described in his textbook on geometry: the ''Elements''. Euclid's approach consists in assuming a small set of intuitively appealing axioms ...
. Sometimes the word ''plane'' is used more generally to describe a two-dimensional
surface, for example the
hyperbolic plane and
elliptic plane.
When working exclusively in two-dimensional
Euclidean space
Euclidean space is the fundamental space of geometry, intended to represent physical space. Originally, that is, in Euclid's ''Elements'', it was the three-dimensional space of Euclidean geometry, but in modern mathematics there are Euclidean sp ...
, the definite article is used, so ''the'' plane refers to the whole space. Many fundamental tasks in mathematics,