A **circle** is a simple shape of Euclidean geometry that is the set of all points in the plane that are equidistant from a given point, the centre. The distance between any of the points and the centre is called the radius.

A circle is a simple closed curve which divides the plane into two regions: an interior and an exterior. In everyday use, the term "circle" may be used interchangeably to refer to either the boundary of the figure, or to the whole figure including its interior; in strict technical usage, the circle is the former and the latter is called a disk.

A circle can be defined as the curve traced out by a point that moves so that its distance from a given point is constant.

A circle may also be defined as a special ellipse in which the two foci are coincident and the eccentricity is 0. Circles are conic sections attained when a right circular cone is intersected by a plane perpendicular to the axis of the cone.

Read more about Circle: Terminology, History, Properties, Circle of Apollonius, Circles Inscribed in Or Circumscribed About Other Figures, Circle As Limiting Case of Other Figures

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**Circle**, Montana - Demographics

... There were 291 households out of which 27.8% had children under the age of 18 living with them, 56.0% were married couples living together, 5.5% had a female householder with no husband present, and 36.1% were non-families. 34.4% of all households were made up of individuals and 19.6% had someone living alone who was 65 years of age or older ...

... Descartes' theorem is most easily stated in terms of the

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**Circle**

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**Circle**... a short but happy period of study, and he assembled a cultured

**circle**, whom the near neighbourhood of the university and his own brilliant qualities attracted to his house ...

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**circle**passing through p and a pair of additional ... This

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### Famous quotes containing the word circle:

“It was my heaven’s extremest sphere,

The pale which held that lovely deer;

My joy, my grief, my hope, my love,

Did all within this *circle* move!”

—Edmund Waller (1606–1687)

“Writing about an idea frees me of it. Thinking about it is a *circle* of repetitions.”

—Mason Cooley (b. 1927)

“To love someone is to isolate him from the world, wipe out every trace of him, dispossess him of his shadow, drag him into a murderous future. It is to *circle* around the other like a dead star and absorb him into a black light.”

—Jean Baudrillard (b. 1929)