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A polygon is a union of disjoint [[line segment]]s that is [[path-connected]].

A polygon is a union of disjoint [[line segment]]s that is [[path-connected]].

Types, by number of sides.

Types, by number of sides.

# There is no such mathematical entity as a one sided polygon in a plane.  (For three dimensional analogies, see [[Mobius strip]] and [[Klein bottle]].)

# There is no such mathematical entity as a one sided polygon in a plane.  (For higher dimensional analogies, see [[Mobius strip]] and [[Klein bottle]].)

# As with the one-sided polygon, there is no such thing as a two-sided polygon.  (This would be two overlapping [[line segment]]s.)

# As with the one-sided polygon, there is no such thing as a two-sided polygon.  (This would be two overlapping [[line segment]]s.)

# [[Triangle]] - see [[isosceles triangle]], [[equilateral triangle]], [[right triangle]]

# [[Triangle]] - three sided, see [[isosceles triangle]], [[equilateral triangle]], [[right triangle]]

# [[Quadrilateral]] -  See also [[square]], [[rectangle]], [[rhombus]], and [[trapezoid]]

# [[Quadrilateral]] -  four sided, see also [[square]], [[rectangle]], [[rhombus]], and [[trapezoid]]

# [[pentagon (geometry)|Pentagon]]

# [[pentagon (geometry)|Pentagon]] - five sided.  The most famous one houses the [[Department of Defense]].

# [[Hexagon]] - the shape of a bee hive cell, also used in some board games

# [[Hexagon]] - six sided, the shape of a bee hive cell, also used in some board games

# [[Heptagon]] - not commonly encountered in everyday life

# [[Heptagon]] - seven sided.  Some coins have been been heptagonal.

# [[Octagon]] - used for [[stop sign]]s in the U.S.

# [[Octagon]] - eight sided, used for [[stop sign]]s in the U.S.

[[Category:Geometry]]

[[Category:Geometry]]