From handles to doughnuts
The theorem of classification of the surfaces states that any compact, connected, orientable surface without boundary can be related to a standard surface. We can visualize these standard surfaces as spheres with some handles attached or, otherwise, as doughnuts with a certain number of holes. The image shows the last step of the construction that proves that these two shapes are equivalent (a doughnut with a hole). See the preceeding step.
© matematita
The image belongs to the sections...:
Standard surfaces (Topology)