The Digital Object Identifier (DOI®) System is used to identify digital resources when referencing them in academic literature. DOIs are widely used by the citations in IEEE and many other journals.

Web addresses can change, but DOIs remain fixed and always point to a particular digital resource regardless of where it lives on the web. You can resolve any DOI simply by prepending http://hdl.handle.net/ and entering the resulting URL in a Web browser. For example, the DOI

  10254/nanohub-r1305.5

can be resolved by following the URL:

  http://hdl.handle.net/10254/nanohub-r1305.5

which takes you directly to a specific version of a particular tool on nanoHUB.