Reason for using SGML/XML

SGML/XML ensures reusability of documents by preserving raw data and content-based structuring of information pieces. Preserving data for statistics and formulas in mathematics and chemistry could allow researchers to reuse and repeat simulations, calculations and experiments, deriving the needed data directly from an archive.

Second, using structured information allows the reuse of the same information or documents in different contexts, i.e., the same digital dissertation can be used to produce an online or print version, and to produce additional information products, like monthly proceedings containing the abstracts of all dissertations produced within the university during the last month, or a citation index. Additionally, the dissertation can be displays for different media, so a Braille reader or an automatic voice synthesizer could be used as a back-end machine.

Another reason for using markup for encoding documents is that a wider, more qualified retrieval could be provided to the users of an archive. As university libraries are more and more challenged by the problem of handling, converting, archiving and providing electronic publications, one of the major tasks is providing a new quality for retrieval within the user interface. Using an SGML/XML-based publishing concept enables a new quality in the distribution of scientific contents via specific information and knowledge management.

What does SGML/XML mean?

The Extensible Markup Language (XML) is the universal format for structured documents and data on the Web. Before XML there was the Standard Generalized Markup Language (SGML) widely used for large documentation projects. SGML was mostly used for technical documentation.

"Structured data", such as mathematical or chemical formulas, spreadsheets, address books, configuration parameters, financial transactions, technical drawings, etc. are usually put on the Web using the output of layout programs as Postscript or PDF or by putting them into graphic formats like gif, jpeg, png, vrml, and so on. Programs that produce such data often also store it on disk, for which they can use either a binary format or a text format. So, if somebody wants to look at the data, he usually needs the program that produced it. With XML those data could be stored in a text format, which allows the user reading the file without having the original program. XML is a set of rules, guidelines, conventions, whatever you want to call them, for designing text formats for such data, in a way that produces files that are easy to generate and read (by a computer).

The Extensible Markup Language (XML) is a markup or structuring language for documents, a so-called meta language, that defines rules for the structural markup of documents independently from any output media. XML is a "reduced" version of the Structured Generalized Markup Language (SGML). It prevail success in technical documentation. The main philosophy of SGML and XML is the strict separation of content, structure and layout of documents.