Learning 3D Objects (Or how to be a master builder)

In one of the lectures, we covered the basic understanding of 3D objects, how to make them, how they help with the final result, and the history of 3D. 
The five was to see and create a 3D sculpt:

Form:Shape/Size/Function/Anatomy
Surface:Surface Texture e.g: Pores,Wrinkles, Scratches, Cracks, Wood-Grains.
Substances:The material the object is made out of e.g: Woods, Metals, Stones
Colour:Defined by the 'Shader' and 'Texture Maps'
Optimisation:For Rendering and Editing e.g: Video making

In the Beginning....

Polygons
3D 'dot-to-dot' which have a finite resolution, more polygons=more information, not very good for topology.
Divisions: 8x4/16x8/32x16
Faces: 32/128/512

NURBS (Non-Uniform Rational B-Splines)
Mathematically calculated curves scaled to an infinite resolution. So annoying to animate, not used in digital sculpting or real-time engines.

Divisions: 8x4/8x4/8x4
(Interpolated)

Subdivision Surfaces 

They are more advanced Polygons and are very easy to manipulate because of the levels of subdivision.  They can be partially or fully creased for hard edges. First used with PIXAR.

Faces: 6/6/6

Subdivided by 2: 6/24/96 (6x1 = 6, 6x4 = 24, 24x4 = 96)

Voxels:

It stands for volumetric Pixel, it's a 3D pixel that is a digital cube that has finite resolution, similar to 'DPI' (Dots per Inch). More points=more information, it's processor and memory intensive, they are barely used in real-time engines, it's used in the game minecraft.

(Minecraft)

Object Components:

Vertex: A single point defined by the XYZ axis and co-ordinates 0.0.0

Edges: A line between two vertices, one edge does not have Volume.

Faces: Geometry that is a single sided surface.

Polygon: Multiple conjoined faces that have 3 versions.

3 sided: Tri (Good), 4 sided: quad (average), 5+ sided: N-Gon (Bad)

NORMALS:Vector: a direction.
Perpendicular at 90° to the surface.
It can be modified to alternative angles in modelling packages.
It can be overridden by a texture file: ‘Normal Mapping’.
But in ZBrush will remain exactly perpendicular to the surface.

Towards ZBrush

It's 'traditional' Digital Modelling done by using Primitives like Cubes, Spheres, Squares etc.
It has lots of ways of production, these are the main three ways for using primitives in ZBrush!

Good

Zspheres: Quick to block out ideas, easy to manipulate/resize and rotate, easy to maintain proportions (especially for limbs)

Dynamesh: Helps you to be creative, it's great for form-finding, plus can be used for 'boolean'.

ShadowBox: it's good for hard surfaces, interim components, 3D silhouettes, and mechanical shapes.

Bad

Zspheres: it has no numerical control, and isn't very good for flat surfaces.

Dynamesh: Steer away from detailing, has bad topology, and will create holes if the resolution is too thin.

ShadowBox: Can't retain a crisp edge because of the resolution.

Ugly

Zspheres: Can be fiddly, and adaptive skin is a real nightmare.

Dynamesh: The harder the surface, the more difficult it is to master.

ShadowBox: Very difficult to 'Pick up'. 

(Zspheres)

(Dynamesh)

(ShadowBox)