The purpose of this guide is to briefly explore the questions:
Metadata are everywhere. As Jenn Riley observes in her primer, Understanding Metadata (NISO, 2017), "Metadata are pervasive in information systems, and come in many forms. [...] Metadata is key to the functionality of the systems holding the content, enabling users to find items of interest, record essential information about them, and share that information with others."
This guide deals with metadata as it is created within a library, or more broadly, a digital collections setting.
The most common definition is that metadata are "data about data." A better definition is that metadata are deliberate, structured data about data.
Metadata are used to facilitate and support resource discovery, identification, the organization of resources, and the exchangeability of the data itself as well as the exchangeability of the resource or resources it represents. Metadata also capture and provide important contextual details, as not all resources are self-describing.
There are many different kinds of metadata. In the world of digital objects, metadata is usually divided into 3 to 5 categories: