What is a prism?
A prism is a solid shape with two ends that are exactly the same and flat. These two matching ends are called the bases. All the sides joining the bases are flat, and if you slice the prism anywhere between the ends, the slice looks the same.
- A cube and a cuboid (like a box) are prisms.
- A triangular prism (like a tent) is a prism.
What is a non-prism?
A shape is a non-prism when its faces are not all flat or its ends do not match. A cylinder has a curved surface, a sphere (ball) is round all over, a cone comes to a point, and a pyramid also comes to a point. So all of these are non-prisms.
Worked example
Is a triangular prism a prism? Its two ends are the same triangle, and its three sides are flat rectangles. Both ends match and every face is flat, so yes, it is a prism. It has 5 faces in all: 2 triangles and 3 rectangles.
Remember
- Prism: two matching flat ends, all flat faces.
- Non-prism: has a curved surface or comes to a point.