What is the term given to the perimeter around a circle?

When studying geometry, students may look into measuring circles. The student will either need to measure parts of the circle or the information should be provided. With this information, the student can calculate the area, perimeter or circumference of the circle. To measure the circumference of a circle, the student would need to multiply the radius by the amount of pi and then multiply that by two.

The circumference is the perimeter around a circle. For example, if the radius is 5, the student would calculate five times 3.14 which is 15.7 and then multiply that by two which is 31.4. The radius is the halfway point from the center of the circle to outer line of the circle. Then with that information, the student can determine the circumference of the circle.