 | We start off with a rotating image of Boy's Surface. Notice how the surface forms three "lobes" as it intersects itself. |
 | Here we see an animation of a thin strip moving along the surface. Notice how it starts out as a circular loop, then crosses in the middle, and joins back up in the shape of a rounded triangle. The shape it forms after crossing once and before joining together is called a trefoil knot. The next picture down illustrates this. |
 | Here is a rotating trefoil knot, one of the shapes which can be found on Boy's Surface. |
 | Finally, we show a rotating image of the part of Boy's surface surrounding the curve of self-intersection. The self-intersection curve forms a three leaf clover shape, with each of the lobes at right angles to the other two. |