From mesh

​ From mesh

The Mesh command creates a polygon mesh from a NURBS surface, polysurface, or SubD.

A mesh is a collection of vertices and polygons that define the shape of a polyhedral object. Rhino meshes consist of triangles and quadrilaterals.

Rhino creates triangles and quadrilateral meshes for exporting to various file formats. If a mesh is generated from a solid, it will be seamless and watertight.

For more information, please refer to the Rhino documentation.