# What Is an Polygon?

## What Is a Polygon?

A polygon is a 2-dimensional shape with straight sides.

### Dictionary Definition

The Oxford English Dictionary defines a polygon as "a plane figure with many (usually more than four) straight sides and the same number of angles."

## Regular Polygons

Regular polygons have sides of equal length and equal angles.

Shape | Name | Number of sides |
---|---|---|

Triangle A regular triangle is an equilateral triangle |
3 | |

Quadrilateral A regular quadrilateral is a square |
4 | |

Pentagon |
5 | |

Hexagon |
6 | |

Heptagon |
7 | |

Octagon |
8 | |

Nonagon |
9 | |

Decagon |
10 | |

Dodecagon |
12 |

## Irregular Polygons

Irregular polygons have sides of different lengths and different angles.

Shape | Name | Number of sides |
---|---|---|

Irregular Quadrilateral | 4 | |

Irregular Hexagon | 6 | |

Irregular Octagon | 8 |