The surface area of a sphere is the total area that covers the outside of the sphere. It can be calculated using the formula 4\pi r^2, where r is the radius of the sphere. The constant \pi (approximately 3.14) is a mathematical constant that relates the circumference of a circle to its diameter. Understanding the surface area is important in various fields, such as physics and engineering, where it helps in calculating materials needed for spherical objects. For example, when designing a ball or a tank, knowing the surface area ensures proper coverage and efficiency in use.