Shapes all have different properties. You may need to use these properties to work out quantities such as the surface area or volume of a specific shape, so it is useful to know how certain shapes differ from others. Rectangles and rectangular prisms seem similar at first glance, but have one crucial difference.

### Rectangle

A rectangle is a two-dimensional object that has four sides. It has two sets of sides with equal lengths, and 90-degree angles in the corners. For example, an object with two opposite sides that are both 1 cm long and two opposite sides that are both 2 cm long is a rectangle. If all four sides are the same length, the rectangle is also a square. You can work out the area of a rectangle by multiplying the length of one side by the length of an adjacent side. In the example, the area would be 1 cm multiplied by 2 cm, which equals two square centimeters. Rectangles only exist in two dimensions.

### Rectangular Prism

A rectangular prism is a three-dimensional object with six faces. The faces themselves are all rectangles or squares and come in pairs. That means a rectangular prism is made of three sets of rectangles that are put together to form a three-dimensional object. It is a prism because it has the same size cross section along the whole length. The cross section of a rectangular prism is a rectangle.

### Number of Dimensions

The main difference between a rectangle and a rectangular prism is that a rectangle exists in two dimensions whereas a rectangular prism exists in three dimensions. A rectangular prism has a width, height and length, whereas a rectangle has only width and length. You can make a rectangular prism out of real material, such as wood, while you might draw a rectangle on a piece of paper.

### Other Differences

Both rectangles and rectangular prisms are made up of rectangles, but a rectangular prism comprises six rectangles, whereas a rectangle itself comprises only one. Rectangles and rectangular prisms are both made out of pairs of shapes of equal size. Rectangles are made of pairs of lines, whereas prisms are made of pairs of rectangles.