The acronym CIF is used both for the Crystallographic Information File, the data exchange standard file format of Hall, Allen & Brown (1991) (see Documentation), and for the Crystallographic Information Framework, a broader system of exchange protocols based on data dictionaries and relational rules expressible in different machine-readable manifestations, including, but not restricted to, Crystallographic Information File and XML.

CIF was developed by the IUCr Working Party on Crystallographic Information in an effort sponsored by the IUCr Commission on Crystallographic Data and the IUCr Commission on Journals, and was adopted in 1990 as a standard file structure for the archiving and distribution of crystallographic information. It is now well established and is in regular use for reporting crystal structure determinations to Acta Crystallographica and other journals. It is often cited as a model example of integrating data and textual information for data-centric scientific communication. In 2006 the importance of CIF and the value of its accompanying web-based service for the validation of structural data, checkCIF, were recognised by the Award for Publishing Innovation of the Association of Learned and Professional Society Publishers (ALPSP). In their report, the judges 'were impressed with the way in which CIF and checkCIF are easily accessible and have served to make critical crystallographic data more consistently reliable and accessible at all stages of the information chain, from authors, reviewers and editors through to readers and researchers. In doing so, the system takes away the donkeywork from ensuring that the results of scientific research are trustworthy without detracting from the value of human judgement in the research and publication process'.

This part of the IUCr web site provides comprehensive documentation and software resources for users and developers of CIF software.