... the trees and makes it possible to build lists and to calculate Gauss Krueger coordinates etc..
Another characteristic is the evaluation of data. The data is organized in trees that consist of objects. These could develop behavior or become of a specific type which then adds behavior to the element. That makes it possible to tranform or define loaded elements, e.g. by RDF, OWL, Schema etc..
The in- and output can be individually selected, e.g. you can use csv or xml.