Streamlining is the shaping of a body so that it meets the smallest amount of resistance as it moves through a fluid (liquid or gas). The best streamlined shape for a body depends on whether it is to travel slower or faster than sound through the fluid. For subsonic (slower than sound) travel, a body should be somewhat blunt and rounded in front, and then taper to a point at the tail. Submarines and subsonic airplanes have this shape. In nature, fish have this type of streamlining. For supersonic (faster than sound) travel, a body should have a pointed front to reduce the effects of shock waves. Engineers design supersonic airplanes and rockets to have this shape.