The surface of a lake represents a <em>plane</em> because it extends in all directions at the same level. Imagine it as a quite surface, without imperfections, smooth and perfectly plane, it is a two-dimensional figure.
A fishing line that enters into the water, crossing the lake's surface, representes a <em>line, </em>which may be either perpendicular or leaned.
Thus the intersection of those two figures is a point.
A surface and a line that is not included in the plane and is not parallel to it will meet at a single point, which is what is represented by the situation stated.
