Area and perimeter are two calculations performed on many geometric shapes. Perimeter is a measure of distance around a shape; for example, someone might want to figure out the perimeter around their garden before buying material to make a fence so that they know how much material to buy. Area is a measure of the amount of surface something covers; for example, someone might want to know how much space their garden takes up. Area and perimeter are often grouped together because one can be used to help you figure out the other. For example, if you know the perimeter of a square, you can easily figure out the area, and vice versa.