Perimeter is an important concept in math and measuring physical spaces. It’s the distance all the way around the outside. It is the total distance around the outside of a shape, like a fence around a garden. If you have a square or rectangle, you can easily find the perimeter by adding up all the sides. For a circle, you need to find the edge’s distance, called the circumference. Knowing the perimeter is useful in many instances such as buying enough materials to build a fence or study of geometry to help you measure shapes.