What is representation information?

Representation information is any information required to understand and render both the digital material and the associated metadata. Digital objects are stored as bitstreams, which are not understandable to a human being without further data to interpret them. Representation information is the extra structural or semantic information, which converts raw data into something more meaningful.

For example, structure information could tell a computer to interpret a string of bits as ASCII characters and semantic information could explain what a particular mathematical symbol means.

Representation information should contain as much structure and semantic information as is required for a defined community (or Designated Community in OAIS terminology) to access the information stored within a digital object.

The term can be applied to all levels of abstraction and refers to both the structural and semantic composition. It can therefore be recursive and is dependent on the knowledge base of the designated community.

Representation information is not the same thing as metadata which describes data in administrative, descriptive, technical, structural and preservation terms. In the Lifecycle model, metadata is covered under the Description term.

For more information on representation information, see