# Introduction

In our environment, we come across different types of geometrical shapes. If you look in detail, you can identify the shapes and how they are used. Polygons can be found almost everywhere. Blackboard in your classroom, Clock, Pencil boxes are some examples.

Roof of our houses, gardens, and land can also be in the form of polygons.

We can find the area, volume and surface area of these shapes. Letâ€™s look at some examples of these shapes.

Geometrical shapes are also used in designing and art.

Famous buildings and Temples are constructed using polygons. For example, look at the picture.

You can identify lot of geometrical shapes in this house. To produce structures that were functional as well as models of architectural beauty, designers had to apply principles of mathematics in their work. Proper ratios and proportions related each feature of a building with every other one and with the whole structure. Various geometric shapes provided maximum use as well as a pleasing appearance in all types of architecture.

**Curves :-**

The following pictures are examples of curves.

A curve is a set of connected points. That is, any set of "dots" that can be drawn without lifting a pencil.

**Simple Curves :-**

A simple curve is a curve that does not intersect itself at any point other than possibly at the endpoints.

**Closed Curve :-**

A closed curve is a curve that begins and ends at the same point.

**Polygons :-**

A polygon is a simple closed curve composed of a finite number of line segments.