A Digital Object Identifier (DOI) is a string of letters and numbers that is used to identify documents and other objects on the internet. A DOI is a persistent identifier, meaning that it will always direct to the same unique object.
A DOI is made up of three parts: a URL which directs to a DOI resolver; a prefix that identifies the organisation that created the DOI; and a suffix, which is unique to the item.

Having a DOI for your research output makes it easier for others to correctly cite your work, and also makes it easier for you to track the impact of your research.
Trinity College Dublin is part of the national DataCite consortium, which allows us to create our own DOIs. We create DOIs for items deposited in TARA, and also for our Digital Collections. Books and manuscripts in Digital Collections are assigned DOIs automatically so that users can confidently cite items accurately and consistently. In TARA, DOIs can be assigned to items on request, and you can find instructions on how to request a DOI below.