# Definition:Euclidean Space/Euclidean Topology/Real Number Plane

## Definition

Let $\R^n$ be an $n$-dimensional real vector space.

Let $M = \struct {\R^2, d}$ be a real Euclidean space of $2$ dimensions.

The topology $\tau_d$ induced by the Euclidean metric $d$ is called the Euclidean topology.

The space $\struct {\R^2, \tau_d}$ is known as the (real) Euclidean plane.

## Also known as

The Euclidean topology is often called the usual topology.

## Also see

• Results about Euclidean spaces can be found here.

## Source of Name

This entry was named for Euclid.

## Historical Note

Euclid himself did not in fact conceive of the Euclidean metric and its associated Euclidean space, Euclidean topology and Euclidean norm.

They bear that name because the geometric space which it gives rise to is Euclidean in the sense that it is consistent with Euclid's fifth postulate.