An viewpoint is simply a unit of content on Goodpoint. Meaning, it's a small bundle of information that we keep in one piece so that the system works right. For example, when you look at an outline, every line is a viewpoint.
The point is essentially a constellation of ideas.
I, 2, and 3 are are viewpoints, just as 1A or 3Biiii are viewpoints. Viewpoints have information inside them, whether they be facts, opinions, or URLs. Taken together, they serve as support for a point.
See also:
The Two Ways to Support an Idea
The Two Places an Idea Can Go in an Outline