The line which appears when we are dragging an object of GUI on a object of windows Form indicates that the object that is being dragged is aligned horizontally with the object which is connected by the blue line is called a snap line.
Hence we conclude that the answer to this question is snap line.
Because you can make it to where they cannot find or see or look or talk or anything on your profile it can cut off Comunication from the person. It can also protect your safety!