3-dimensional shapes
3-dimensional (3D) shapes are solid shapes. They have 3 dimensions - Distance from one end to the other. How long something is, its longest dimension., The measurement of something from side to side. and The shortest distance between the base of a geometric figure and its top, whether that top is an opposite vertex or another base..
Vertices, edges and faces
Some 3D shapes have faces, edges and vertices.
- A face is a flat surface.
- An edge is where two faces meet.
- A vertex is a corner where edges meet. The plural is vertices.
A prism is a 3D solid with a uniform cross-section. The two end faces of a prism are identical in shape and size. If you make a cut parallel to the ends, the cross-section exposed will be the same shape and size as the ends.
A pyramid has a polygon as its base and the rest of its faces are triangles that meet at the same vertex.
Here are some common 3D shapes.
| Name | Faces | Edges | Vertices |
| Cube | 6 (all squares) | 12 | 8 |
| Cuboid | 6 (all rectangles) | 12 | 8 |
| Square-based pyramid | 5 | 8 | 5 |
| Triangular-based pyramid | 4 | 6 | 4 |
| Name | Cube |
|---|---|
| Faces | 6 (all squares) |
| Edges | 12 |
| Vertices | 8 |
| Name | Cuboid |
|---|---|
| Faces | 6 (all rectangles) |
| Edges | 12 |
| Vertices | 8 |
| Name | Square-based pyramid |
|---|---|
| Faces | 5 |
| Edges | 8 |
| Vertices | 5 |
| Name | Triangular-based pyramid |
|---|---|
| Faces | 4 |
| Edges | 6 |
| Vertices | 4 |
Some 3D solids, such as the cone and the cylinder, have faces and curved surfaces.
Some 3D solids, like the sphere, just have a curved surface.