Lange's Basic Data model of Hypertext

In the simplest form, hyperdocument can be modeled as a set of nodes and a collection of links. Documents can be modeled as nodes and cross-references are links. So the meaning of hyperdocument is defined as a database that has cross references which allows the user to access the text non-sequentially.

Nodes

Nodes are collection of fragments of information in the hypertext document. The fragments are named distinctly and may be assigned explicitly, either manually or automatically by user. Attributes are needed in order to be able to give name to the node. Nodes can also be divided into several types, such as: document, figures, annotations, etc. The structure of a node can be compared to a record datatype in programming languages.

Slots

Each nodes has collection of slots, these are uniquely named. Slot can be use to represent structured information, like in relational database.

Links

Links connect nodes in the hypertext document. The hypertext network is made up of a collection of links that each links has unique name. In concept, link is directed; it has source (origin) and an end point (destination).

Hypertext system allows different types of links. These links have attributes as well as nodes. The purpose is to reflect the type of information a link is pointing to.