The circumference is the distance around the edge of a circle. It can be calculated using the formula C = 2\pi r , where C represents the circumference, r is the radius, and \pi (approximately 3.14) is a constant that represents the ratio of the circumference to the diameter of any circle. Understanding circumference is important in various fields, including geometry and engineering. It helps in measuring circular objects, such as wheels or pipes, and is essential for tasks like determining the length of fencing needed for a circular garden or the distance traveled by a rotating wheel.