
Geometrically, a Moebius band is an infinitely thin,
single-sided surface with a single contour.
Most often it is represented by a belt with a half twist.
The key feature is that when we scoot along the surface of the belt,
we will have to make two loops around the length of the belt
in order to come back to the same position from where we started;
furthermore, half-way through this path, we visited the spot
on the opposite side of the belt surface.
thank god for berkeley