Hi Brian,

> The difference between Points and Vectors, and their
> display, is confusing to me.
> I'm thinking Points are displayed as the endpoints of
> vectors, from some origin, and vectors are displayed as
> start and end points...

Well, both points and vectors are represented by the same data - a triplet of x,y,z data.

The difference is the way that data is interpreted - for a point the x,y,z is meant to indicate a specific location in space.

For a vector the x,y,z is meant to represent a direction rather than a position.

Search for something like "vector algebra" to see examples, like:
http://emweb.unl.edu/math/mathweb/vectors/vectors.html

- Michael