Closed curve
A closed curve is a curve with no endpoints.
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A closed curve flows continuously with no breaks or gaps. It forms a shape with a region or regions that have area. A closed curved can be made of curves and line segments. When drawing a closed curve, the starting point and ending point are the same point. A closed curve is the opposite of an open curve, which has two or more endpoints. The following are a few examples of open curves.
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Types of closed curves
There are two types of closed curves.
Simple closed curves
A simple closed curve is a closed curve that does not intersect anywhere except at its beginning point and end point.
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Each figure above is a simple curve. None of these simple curves cross over themselves.
Non-simple closed curves
A non-simple closed curve is a closed curve that intersects itself at more than just its beginning point and endpoint. A non-simple closed curve creates two or more distinct regions.
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Each of the three non-simple curves above overlaps at least one time.