The simplest way to access files in a NODAL repository is via the top-level file system interface. This interface presents a very traditional hierarchical filesystem view of the repository, with directories containing both other directories and files, both identified by locally unique names. A file can thus be identified with a unique URI identifying the repository, a directory path and the selected file.
The basic unit of a document graph is the Node and each node in a particular repository has an associated, unique identifier called the Node ID or NID.
A second means of identifying nodes in a repository is by a user-associated Name which is unique within a particular file. The URI of the file thus identifies a Namespace and the Name is associated with a particular Node in that file.