In mathematics, the Klein bottle was a non-orientable surface, informally, a surface with no identifiable "inner" and "outer" sides. A Klein bottle had no boundary. For comparison, a sphere was an orientable surface with no boundary.
In mathematics, the Klein bottle was a non-orientable surface, informally, a surface with no identifiable "inner" and "outer" sides. A Klein bottle had no boundary. For comparison, a sphere was an orientable surface with no boundary.