Shapes: An Introduction

Shapes are an important concept in mathematics and geometry. They are defined by their boundaries and can be classified into various categories based on their properties. Some common shapes include squares, triangles, and circles. However, there are certain objects or concepts that do not fall under the category of shapes. One such example is sound.

Shapes
Shapes are defined as two-dimensional figures that are enclosed by boundaries. They can be identified by their sides, angles, and other characteristics. Let's explore the shapes mentioned in the options:

- Square: A square is a quadrilateral with four equal sides and four right angles.
- Triangle: A triangle is a polygon with three sides and three angles.
- Circle: A circle is a perfectly round shape with no straight sides or angles.

Sound: Not a Shape
Sound, on the other hand, is not a shape. It is a form of energy that travels through a medium, such as air or water, in the form of waves. Sound is perceived by our ears and interpreted by our brains. It does not have a physical form or boundaries that define its shape. Therefore, sound cannot be categorized as a shape.

Conclusion
Shapes are two-dimensional figures that can be identified by their boundaries and properties. While squares, triangles, and circles are examples of shapes, sound is not a shape. It is a form of energy that travels through a medium in the form of waves. Understanding shapes is important in mathematics and geometry as they form the foundation for further learning in these subjects.