What Is XML?

SGML is the Standard Generalized Markup Language (ISO 8879:1985), the international standard for defining descriptions of the structure of different types of electronic document.

XML is derived from SGML and stands for Extensible Markup Language. XML is a human-readable, machine-understandable general syntax for describing hierarchical data, applicable to a wide range of applications (databases, e-commerce, Java, Web development, searching, and so on). XML is smart data, or data that has the capability to describe itself. Whereas HTML tells you how data should look, XML tells you what the data means. This is a substantive difference. HTML tags, for example, tell you how the data should be represented in a browser, and you must use ...

Get PowerBuilder® 9: Internet and Distributed Application Development now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.