We want objects (or better, their abstractions called classes) connected with others, in according to their features and reciprocal relationships.
This last sentence cannot be particular rather than general because is adaptable to many situations: if you want to create a simulation game of social interactions then software's vision rises up, but if you're interested in real social aspect then modeling assumes another taste (even if parallel to the first).
At this point you're beginning to understand that UML is focused on behavioral aspects and on interactions between subjects: you're right.
What you probably don't know is that UML offers more kind of views and diagrams in order to cover how much situations are possible, in a manner that general views are interconnected with particular ones inside the project.
This is not the right place to describe UML 2.0 even on surface; many sites contains good stuff which to start with.
Our goal is to make you know a tool to transform your ideas into schemes with relations.
BOUML is a good one, and this is why we strongly suggest to see it on work from the video below (long but clear and auto explicative).
Beauty of this kind of tools is availability of extensions to transform your modeling job into code: BOUML supports C++, Java, PHP and others.
So try it, take confidence even if you don't need to write code: modeling is a high level, logical and associative vision.
It's much closer to human language than any other programming one.
Be curious and try it, and as always we see on next article!