Introductory of 3D Shapes

Before we proceed to 3D shapes, lets have a glance on 1D and 2D shapes first.

This is a line which has 1 dimension, that is length.

A rectangle however has 2 dimensions,  which are length and breadth. So it is a 2D shape.

Other examples are squares, circles, triangles, parallelograms and all the polygons such as hexagon, pentagon etc. They have area but no depth

Let's have a look at some 3D shapes below:

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A  cube	A cuboid

A  cylinder	A cone
A  triangular prism	A pyramid

So all 3D shapes must have depth to make them solid and all 3D shapes have volume.

As a conclusion, a 3D shape is a solid which encloses a volume and has length, breadth and height.