Hash-URI resources do not have well-defined semantics. In HTML, they are typically used to take the user to a particular point on the page, and are also sometimes used to record application state. In XML and semantic web use, they are used as identifiers that are distinct from the base resource (i.e., without the hash URI fragment), but often contained in the same document (e.g., an RDF/XML element with the corresponding id attribute). In Fedora, they are intended to be resources that are distinct from but dependent on the base resource.
Current implementation - as JCR Nodes
In the current implementation, hash URI fragments are stored on JCR nodes under a special node named #. So properties about the hash URI fragment /foo#bar would be attached to the node /foo/#/bar.
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