3-D Modeling
by literally drawing the image using x-y-z coordinate planes
and then using polygons to create a wire-frame or mesh
outline of the object
The evil terminator in "Terminator 2" was created this way.
Approximating the object with splines, - essentially curves
similar to those in drawing packages.
Spline-based models often "bend" into more realistic shapes than wire-frame models
The Tyrannosaurus in "Jurassic Park" was created this way.
Fundamentals of 3-D.
3-D Modeling
Adding color, texture etc. to 3-D models.