What is a Digital Object Identifier (DOI)?

A digital object identifier is a persistent identifier for an intellectual object such as a journal article in an electronic environment. Ultimately, as the DOI system matures, the DOI will be a clickable link similar to a URL, but will link to an object (e.g., a journal article) rather than a location (e.g., American Chemical Society).

The numbering system for the DOI consists of two parts, the prefix and the suffix, separated by a forward slash, e.g. prefix/suffix. The prefix is assigned by the DOI system to an organization that wishes to register, such as a publisher (All DOIs begin with 10).

Prefix      Suffix 10.1161/01.CIR.0000143078.48699.0C

The registrant assigns the suffix, which represents a specific intellectual object, such as a journal article. Registrants may use any convention for assigning the suffix portion of the DOI. The suffix may be descriptive of the object, or not.

In the following example, the 1371 is the registrant number assigned to the publisher, which in this case is the Public Library of Science. The registrant devises the scheme for numbering each intellectual object in the suffix. In this case, the object is article 391 in volume 2 of the journal PLoS Biology.

10.1371/journal.pbio.0020391

This is the DOI for an article by A. Athanasiadis, et al. as illustrated by this citation.

Athanasiadis, A., Rich, A., and Maas, S. (2004). Widespread A-to-I RNA editing of Alu-containing mRNAs in the human transcriptome. PLoS Biol. 2, e391. 10.1371/journal.pbio.0020391. Citation from Cell

Sometimes the numbering scheme in the suffix is not readily apparent, as in the following example of a DOI for an article appearing in the Journal of Biological Chemistry.

10.1074/jbc.M501052200

This is the DOI for an article by Z. Beharry and T. Palzkill as illustrated by this citation.

Beharry, Z. and Palzkill, T. (2005). Functional analysis of active site residues of the fosfomycin resistance enzyme FosA from Pseudomonas aeruginosa. J. Biol. Chem. 280, 17786-17791.

For more information and to resolve this DOI see The Digital Object Identifier System.