The surface area of a cylinder is the area of the two bases, both circles plus the area of the part in the middle. Think of a soda can, generally cylindrical in shape. That part that you hold around middle of the can, if you could peel off the put flat, would be a rectangle. You can also think of it as the height of the cylinder times the circumference of the top or bottom. So a formula could be 2Pi(r)^2 (area of top and bottom) plus h(2Pi)(r) , area of the part around the middle.