Define: 3D Modeling Terminology :-)

Key 3D Modeling Terminology to Master:

Polygon geometry

Polygons are the most commonly used geometry type in 3D. While polygons are commonly used for all types of objects, in order to create very smooth surfaces with polygons means that you’d need to add a lot more geometry than you would with either NURBS or subdivision surfaces.

NURBS surfaces

NURBS stands for non-uniform rational b-spline (NURBS). NURBS are commonly used for very smooth objects because they don’t require as many points to create the same look as polygon geometry would. A NURBS surface always has four sides that are defined by control points.

Subdivision surfaces

Subdivision surfaces, which are sometimes referred to as NURMS (non-uniform rational mesh smooth), are closely related to polygonal geometry. Subdivision surfaces use an algorithm to take polygon geometry and smooth it automatically. For example, in the image above you can see the polygon cage (the cube shape) around the smoothed subdivision surface (the spherical shape inside the cube). You can think of a subdivision surface as a mix of polygonal and NURBS geometry.

Faces

A face is the most basic part of a 3D polygon. When three or more edges are connected together, the face is what fills in the empty space between the edges and makes up what is visible on a polygon mesh. Faces are the areas on your model that gets shading material applied to them.

Vertex

A vertex is the smallest component of a polygon model. It is simply a point in 3D space. By connecting multiple vertices (the plural of a single vertex) together you can create a polygon model. These points can be manipulated to create the desired shape.

Edges

An edge is another component of a polygon. Edges help define the shape of the models, but they can also be used to transform them. An edge is defined by two vertices at their end points. Together, vertices, edges and faces are the components that all help to define the shape of a polygonal object.


Topology
Whatever type of geometry you use it will either be created by NURBS, or points, edges, and faces. The way these components are connected together and the flow around the 3D object is the topology. You can think of topology as the type of polygon faces, the type of vertices and the flow of the edges.


Triangle
A triangle is the simplest polygon that is made up of three sides or edges connected by three vertices, making a three sided face. When modeling, triangles are typically a polygon type often avoided. When creating complex meshes, triangles tend to pose a problem when subdividing geometry to increase resolution, and when a mesh will be deformed or animated.


Normals
Surface normals are used by your 3D application to determine the direction that light will bounce off of geometry. This is very helpful to get control over how the light reacts to certain materials on your 3D objects.

.....;;;;;;;;;;;............