You can display a camera as an object in a view and use the standard manipulators to move it. This is like holding a camera through which you are not looking and moving it from one place to another (from a bag to a table for example); your hands are the manipulator. Moving a camera this way is particularly useful if you want to see the camera’s path or adjust frustum or clipping planes, for example.
To move a camera while looking through it, see Aim a camera.