3.1 Limitations of SGML
- SGML allows cross-referencing
within the same document. This can be done by assigning unique
identifiers to elements that need to be referred to elsewhere. However,
the uniqueness of the identifier (and hence, the element) is applicable
only within the current local document. Hence, only elements within the
same document (and only those having unique identifiers) can be linked.
Therefore, this mechanism can only be used in a hypertext document to
refer to elements within the same document and not other documents.
- SGML cannot support time dependent data such as audio, and video and also graphics and
images. Rendering of events is not possible in SGML, that is, displaying
a map of NY(New York) and a link that zooms into Manhattan.
The next topic is: Limitations of ODA and possible modifcations.