The two branches of Geometry are:
Plane Geometry - is all about shapes like lines, circles and triangles ... Shapes that can be drawn on a flat surface called a Plane (it is like on an endless piece of paper)
Solid Geometry - is the geometry of three-dimensional space, the kind of space we live in ...
Three Dimensions
It is called three-dimensional, or 3D because there are three dimensions: Width, depth and height.
There are two main types of solids, "Polyhedra", and "Non-Polyhedra":
Polyhedra
A polyhedron is a solid made of flat surfaces. Each surface is a polygon. Examples:
Platonic Solids
Prisms
Pyramids
Non-Polyhedra
Some solids have curved surfaces, or a mix of curved and flat surfaces (so they aren't polyhedra). Examples:
Sphere
Torus
Cylinder
Cone
Plane Geometry - is all about shapes like lines, circles and triangles ... Shapes that can be drawn on a flat surface called a Plane (it is like on an endless piece of paper)
Solid Geometry - is the geometry of three-dimensional space, the kind of space we live in ...
Three Dimensions
It is called three-dimensional, or 3D because there are three dimensions: Width, depth and height.
There are two main types of solids, "Polyhedra", and "Non-Polyhedra":
Polyhedra
A polyhedron is a solid made of flat surfaces. Each surface is a polygon. Examples:
Platonic Solids
Prisms
Pyramids
Non-Polyhedra
Some solids have curved surfaces, or a mix of curved and flat surfaces (so they aren't polyhedra). Examples:
Sphere
Torus
Cylinder
Cone