Formats for digital preservation: A review of alternatives and issues

Digital formats are acceptable means of preserving Government information. However, with the variety of digital formats available, the question arises as to which format should be used. Therefore, CENDI, an interagency group of scientific and technical information managers within the US Government, reviewed alternative digital formats and the issues related to them. The study was conducted in the interest of implementing best practices in information life-cycle management, to dispel any misunderstandings related to digital formats, and to provide scientific and technical information agencies with enough information so they can determine the most appropriate preservation format for their environment. Four formats commonly used or being considered for use by CENDI agencies and other organizations for preserving documents, TIFF, PDF, PDF/A, and XML, were reviewed. A previous assessment of these formats, which was conducted by the Library of Congress (LC) as part of a more comprehensive evaluation of LC collections, is put in the context of the CENDI agencies. The technical, quality, and functionality factors are described as part of a framework for deciding the appropriateness of a particular format or multiple formats. The decision about the appropriate format is an important component of a preservation plan that must be balanced with other components such as available resources and sustainability.