Digital object identifier, an international standard for document identification
A DOI name takes the form of a character string divided into two parts, a prefix and a suffix, separated by a slash. The prefix identifies the registrant of the name, and the suffix is chosen by the registrant and identifies the specific object associated with that DOI. Most legal Unicode characters are allowed in these strings, which are interpreted in a case-insensitive manner.
For example, in the DOI name 10.1000/182, the prefix is 10.1000 and the suffix is 182. The "10." part of the prefix identifies the DOI registry, and the characters 1000 in the prefix identify the registrant; in this case the registrant is the International DOI Foundation itself. 182 is the suffix, or item ID, identifying a single object (in this case, the latest version of the DOI Handbook). CrossRef, a major DOI registration agency, once recommended displaying DOI names using a URI scheme (for example, doi:10.1000/182), but this practice has been abandoned in favor of a URL (for example, http://dx.doi.org/10.1000/182). This URL provides the location of an HTTP proxy server which will redirect web accesses to the correct online location of the linked item.
DOI names can identify creative works (such as texts, images, audio or video items, and software) in both electronic and physical forms, performances, and abstract works such as licenses, parties to a transaction, etc. The names can refer to objects at varying levels of detail: thus DOI names can identify a journal, an individual issue of a journal, an individual article in the journal, or a single table in that article. The choice of level of detail is left to the assigner, but in the DOI system it must be declared as part of the metadata that is associated to a DOI name, using a data dictionary based on the indecs Content Model.
