What is a Cuboid?

Cuboids, Rectangular Prisms and Cubes 

A cuboid is a box-shaped object. 

It has six flat sides and all angles are right angles. 

And all of its faces are rectangles. 

It is also a prism because it has the same cross-section along a length. 

In fact it is a rectangular prism. 

Examples of Cuboids 

Cuboids are very common in our world, from boxes to buildings we see them everywhere. You can even fit them inside other cuboids! 

Examples of cuboids around us

A box with a slot cut as a handle 

Cuboids in a cuboid room 

Boxes for model trains 

Volume and Surface Area 

The volume of a cuboid is found using the formula: Volume = Height × Width × Length Which is usually shortened to: V = h × w × l Or more simply: V = hwl

Surface Area 

And the surface area is found using the formula: A = 2wl + 2lh + 2hw 

Example: Find the volume and surface area of this cuboid. 

V = 4×5×10 = 200 A = 2×4×5 + 2×5×10 + 2×10×4 = 40+100+80 = 220 

Square Prism 

When at least two of the lengths are equal it can also be called a square prism. (Note: this doesn't stop it from also being called a rectangular prism if you want!) 

Cube 

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f all three lengths are equal it can be called a cube (or hexahedron) and each face will be a square. A cube is still a prism. And a cube is one of the Platonic Solids. So: A cube is just a special case of a square prism, and A square prism is just a special case of a rectangular prism, and They are all cuboids!