Hemisphere:
A 3D geometric object/shape is made up of half of a sphere, with one
side being flat and the other being a bowl-like shape.
2-D and 3-D shapes: Plane figures are of two dimensions (2-D)
and the solid shapes are of three dimensions (3-D).
Edges: The two faces of a solid meet in a line. This line is
called edge.
Vertices: The point at which edges of a solid meet is called
vertices.
Faces: The flat part of a solid is called its face.
Polyhedrons: A three-dimensional shape with flat polygonal faces,
straight edges and sharp corners or vertices is called a polyhedron.