16.4 XML
HTML is fixed; that is, HTML has a predefined set of tags and each tag has its own semantics (meaning). HTML specifies how the information in a web page should be formatted, but it doesn’t really indicate what the information represents. For example, HTML may indicate that a piece of text should be formatted as a heading, but it doesn’t specify what that heading describes. In fact, nothing about HTML tags describes the true content of a document. The Extensible Markup Language (XML) allows the creator of a document to describe its contents by defining his or her own set of tags.
XML is a metalanguage. Metalanguage is the word language plus the prefix meta-, which means “beyond” or “more comprehensive.” A metalanguage goes beyond a ...
Get Computer Science Illuminated, 7th Edition 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.
