Ontologies and Maps
Ontologies are the knowledge structures that underlie semiotic representations, from everyday culture to digital libraries to corporate portals to personal collections. Maps are oriented spatial representations of knowledge.

Interface Ecosystems
The interface can be modeled as a an ecosystem: connected, dynamic, and characterized by relationships. The model is predicated on a process of working with the interface as a border zone between heterogeneous systems of representation.

Dynamic Navigation
Navigation is a set of information elements that represent where we are , and affordances that represent where we can go. Dynamic navigation uses focus+context techniques to respond to gesture, helping the user cope with collections that may otherwise seem like too much information.

XML and DOM
XML is a markup language for representing data and the structure of data through the use of the Document Object Model (DOM). The DOM is a standard means for representing and manipulating documents which adopt its specifications such as HTML and XML.