Sphere, ellipsoid, torus, paraboloid, hyperboloid are shapes with only curved surfaces.
Hemisphere, quadrant, cone and cylinder are examples of shapes with curved and plane surfaces.
There are, of course, many others.
Chat with our AI personalities
Each face of a polyhedron must be a polygon: a flat surface bounded by straight lines. So, if any of the faces is curved, the shape is not a polyhedron.
A hexagon...
PYRAMID
Pyramids have some triangular faces.
This shape has 2 opposite identical faces and some other which are parallelograms is a prism. A cylinder shape has 2 circular faces and one curved face.