DOI stands for Digital Object Identifier, a system to unambiguously identify - and thereby, be able to reliably cite - creative and research outputs. It was developed in the late 1990s, and implemented in the early 2000s, primarily and originally for articles in scholarly journals. For some examples of the use of DOIs in citing sources, see How to Use the New DOI Format in APA Style; and for more details on the DOI infrastructure, the Key Facts on the Digital Object Identifier System.) Since those early years, DOIs have also become adopted for datasets and other research outputs.
DOIs are (intended to be) globally unique, persistent identifiers.
As of Dec. 2016, American University Library generates and maintains DOIs for selected items in its Digital Research Archive. An example is the Constitutionalism and Democracy Dataset at http://doi.org/10.17606/M63W25:
In the "scholarly ecosystem" depicted here:
several questions may be asked by the parties involved, and from the outside:
by the university (for scholarly productivity or promotion and tenure review): what scholarly outputs has this researcher created and published? What do we need to do to accommodate his/her research output?
by funding agencies: what publications and datasets have been generated by this researcher's work that has been funded by us?
by publishers (of articles, books, etc.): how can we and our publications' readers find and identify the researcher, and research data, "behind" this publication?
by researchers: how can I easily list and cite my publications, datasets, funding sources?
by other researchers: how can I find out which dataset or datasets informed the findings in this publication? What publications resulted from this dataset I discovered?
The combination of Digital Object Identifiers (DOIs) for datasets and publications, and ORCID IDs for researchers and research contributors can help establish these linkages easily and unambiguously. (Persistent Identifiers for organizations and funding sources are in development, but beyond the scope of this guide.)
Source of graphic: presentation Linking research data and publications: a survey of the landscape in the social sciences at the Second Workshop on Linking and Contextualizing Publications and Datasets, Sep. 12, 2014.