Any EF-S lens is designed specifically for the crop sensor size of various Canon digital cameras. The EF-S lenses extend further back into the camera and can damage the mirror on a full-frame camera. The 5D has a full-frame sensor making it incompatible with any EF-S lenses.
Also, the crop sensor cameras can us any EF or EF-S lens...but you have to multiple the zoom range by the crop factor (most are 1.6x). So an EF lens listed as a 50mm is actually equivalent to 80mm on a crop sensor camera (1.6 * 50mm = 80mm).