What is metadata?

Metadata describes what your data is, how others can use it, and how it is physically put together. It allows other researchers to determine how, when, where, why and by whom the data was originally produced or collected.

Metadata may be stored as XML, in an accompanying document, a set of data fields in a repository, or a README file. Metadata is generally broken down into three different kinds:

Descriptive metadata

This type enables a dataset to be discovered and identified. Examples include a project title, a description of the research scope, an abstract, and relevant keywords. In many disciplines, controlled vocabularies and nomenclature exist to describe data.

Administrative metadata

This type helps manage the dataset. It includes rights management, access control, use requirements, technical data on file creation and quality control, file formats, software/hardware for access and use, and any information relevant to archiving and preservation.

Structural metadata

This type describes how items relate to one another, e.g. that chapter 1 comes before chapter 2 in a book, or that file x is the JPEG format of the archival TIFF image file z.

Why is there a need for metadata?

For data to be successfully stored, managed, shared and re-used throughout its life cycle, documentation and description of the data is essential. Documentation and metadata requirements will vary according to discipline and the nature of the research being done. Metadata and other necessary documentation to make data usable by and discoverable by others should be identified during data management planning.

Elements of metadata

Metadata is usually structured according to existing standards or 'schemas'. The most common metadata schema is probably Dublin Core, developed in 1995.

Simple Dublin core involves 15 elements, all of which are optional and repeatable, and which can appear in any order:

The following list of standards and schemas is not exhaustive, but will provide some guidance about the appropriate schemas and standards in current use in some disciplines.