SGMLstä

SGML stands for Standard Generalized Markup Language. It is a meta-language used to define markup languages. SGML provides a way to specify the structure and semantics of a document independently of its presentation. This means that the same SGML document can be displayed in many different ways, for example, as a printed book, an online web page, or a speech synthesis output. SGML itself is not a markup language but a standard for creating them.

One of the key features of SGML is its ability to define document types. A document type definition (DTD) specifies the elements, attributes, and relationships that are allowed within a particular type of document. This allows for the creation of highly structured and predictable documents. For example, a DTD for a technical manual would define elements like section, paragraph, figure, and code, along with their permitted nesting and attributes.

SGML was developed by a committee of the International Organization for Standardization (ISO) and published as ISO 8879 in 1986. Its influence has been significant, particularly in the areas of document publishing, data interchange, and technical documentation. While SGML itself is complex and less commonly used directly today, its principles have heavily influenced its descendants, most notably HTML (HyperText Markup Language) and XML (eXtensible Markup Language). XML, in particular, simplifies many aspects of SGML and has become the de facto standard for data markup and interchange on the web and in many other applications.