Frequently Asked Questions
XML is a markup language for documents containing structured information, A markup language is a mechanism to identify structures in a document, The XML specification defines a standard way to add markup to documents.
XML is a markup language for documents containing structured information.Read more
No. In HTML, both the tag semantics and the tag set are fixed. The W3C, in conjunction with browser vendors and the WWW community, is constantly working to extend the definition of HTML to allow new tags to keep pace with changing technology and to bring variations in presentation (stylesheets) to the Web. However, these changes are always rigidly confined by what the browser vendors have implemented and by the fact that backward compatibility is paramount. In addition, for people who want to disseminate information widely, features supported by only the latest releases of Netscape and Internet Explorer are not useful.Read more
No. Well, yes, sort of. XML is defined as an application profile of SGML. SGML is the Standard Generalized Markup Language defined by ISO 8879. SGML has been the standard, vendor-independent way to maintain repositories of structured documentation for more than a decade, but it is not well suited to serving documents over the web (for a number of technical reasons beyond the scope of this article). Defining XML as an application profile of SGML means that any fully conformant SGML system will be able to read XML documents. However, using and understanding XML documents does not require a system that is capable of understanding the full generality of SGML. XML is, roughly speaking, a restricted form of SGML.Read more
In order to appreciate XML, it is important to understand why it was created. XML was created so that richly structured documents could be used over the web. The only viable alternatives, HTML and SGML, are not practical for this purpose.Read more
XML is defined by a number of related specifications:Read more