Surface area is the sum total of all of the surfaces of a solid three dimensional geometric shape. For a cube, the calculation is simple. The surface of a cube is composed of six squares (four sides, a top, and a bottom) each with sides labelled s. The area of one square is s*s or s^2. So multiply this by 6 to get the surface area of the cube (6s^2). The surface area of a sphere is 4pi*r^2. The surface area of a cylinder is 2pi*r(h+r). So you can see that the formula to find the surface area greatly depends on the specific geometry of the shape you are dealing with.