Schema-less structural links in MediaDesc

The maintenance of links in hypermedia documents is a well known problem; research level authoring systems address this problem by means of structural links, which require the definition of a formal schema of the document; this kind of approach discourages rapid prototyping and forbids bottom up development-which is often preferred to a top down approach by authors such as artists and designers. On the other hand commercial authoring systems address the the maintenance of links in hypermedia documents very poorly. On the contrary MediaDesc structural links can exploit regularities in the document structure without forcing the author to define a document schema. MediaDesc structural links can describe sophisticated navigation patterns for well structured documents while, at the same time, authors are not forced to use a complicated document structure if they just need a trivial navigation pattern. Finally we show that MediaDesc authors can start writing a hyperdocument without defining a precise structure and switch to a more structured approach at a later stage with a reasonable effort