don't no
no shape
a face
Possibly a face - or an edge. It would help if the question was properly phrased.
Cylindrical shape or Cylinder shape
don't no
no shape
A sphere
A blob.
a line
A Moebus strip.
Circle. Sphere.
It is a face.
Mobius strip
An edge.
a face
To answer this question more details need to be provided. For example one a 3D shape one side is called a face.