Section 9.1. Metadata

9.1. Metadata

When it comes to definitions, metadata is a slippery fish. Describing it as "data about data" isn't very helpful. The following excerpt from Dictionary.com takes us a little further:

In data processing, meta-data is definitional data that provides information about or documentation of other data managed within an application or environment. For example, meta-data would document data about data elements or attributes (name, size, data type, etc.) and data about records or data structures (length, fields, columns, etc.) and data about data (where it is located, how it is associated, ownership, etc.). Meta-data may include descriptive information about the context, quality and condition, or characteristics of the data.

While these tautological explanations could lead us into the realms of epistemology and metaphysics, we won't go there. Instead, let's focus on the role that metadata plays in the practical realm of information architecture.

Metadata tags are used to describe documents, pages, images, software, video and audio files, and other content objects for the purposes of improved navigation and retrieval. The HTML keyword meta tag used by many web sites provides a simple example. Authors can freely enter words and phrases that describe the content. These keywords are not displayed in the interface but are available for use by search engines.

<meta name="keywords" content="information architecture, content management,  knowledge management, user experience">

Many companies today are using metadata in more sophisticated ways. Leveraging content management software and controlled vocabularies, they create dynamic metadata-driven web sites that support distributed authoring and powerful navigation. This metadata-driven model represents a profound change in how web sites are created and managed. Instead of asking, "Where do I place this document in the taxonomy?" we can now ask, "How do I describe this document?" The software and vocabulary systems take care of the rest.