iRODS allows users and administrators to access and contribute descriptive information about their data (metadata). This metadata improves the search experience and therefore enables data discovery. Users can search for data objects using any metadata descriptor as search terms. Both automatic, system-generated metadata and user-created metadata are supported in iRODS.
What is metadata?¶
Metadata is often called data about data. It describes the data in some way, such as providing information about the content, context of its origin or use, quality, condition, and associations to other data and objects. Metadata can describe a collection, a file or a component of file. Metadata can be embedded in a data object, or stored in a database and linked to the object it describes. Metadata is used to facilitate data discovery to improve search and retrieval.
Scholars classify metadata into three categories: descriptive, structural, and administrative. Descriptive metadata is intended to support data discovery and identification. Title, abstract and keywords are some example to descriptive metadata. Structural metadata describes the structure of the data object. For example, title page, chapters, how pages are ordered, number of pages, etc. Administrative metadata is intended to facilitate management and processing of the data. Identifying how the data was created, its file type, resolution, copyright information, licensing information, access privileges are some administrative metadata examples.
Metadata serves a variety of purposes, with resource discovery one of the most common. Here, it can be compared to effective cataloging, which includes identifying resources, defining them by criteria, bringing similar resources together and distinguishing among those that are dissimilar. It is also a means of facilitating interoperability and integrating resources. Using metadata to describe resources enables its understanding by humans as well as machines. In addition to supporting data discovery, metadata also organizes and provides contextual and historical information about data objects, identifies structural relationships within and between data objects.