There are 4 main identifiers used in Academic publishing. These are essentially numbers used to uniquely identify people and publications.
An orcid id is a unique and persistent number that is applied to a researcher. Every researcher should register for an orcid number (https://orcid.org) and consistently put the id number on his/her publications. Computers understand numbers so will gather all your publications together under your orcid id which in turn keeps all your citations together and improves your metrics. There are other identifiers that you can use such as Scopus ID and Researcher ID but Orcid is rapidly becoming the standard. Remember to populate your record with your biography, work history and attach your publications as the orcid registry can be searched under people’s names.
DOI (Digital Object Identifier)
A DOI, or Digital Object Identifier is a string of numbers, letters and symbols used to uniquely identify an article or document, and to provide it with a permanent web address (URL). You can search for a publication just using the doi. You should ensure that all your articles have a digital object identifier. This is normally applied by the publisher at the time of publication. If you are publishing material in TU Dublin, the library can mint a doi for you.
An ISBN is an International Standard Book Number and obviously, only applies to books. ISBNs were 10 digits in length up to the end of December 2006, but since 1 January 2007 they now always consist of 13 digits. ISBNs are calculated using a specific mathematical formula and include a check digit to validate the number. If you are publishing a book in TU Dublin the library can supply you with an ISBN.
An ISSN is an 8-digit code used to identify newspapers, journals, magazines and periodicals of all kinds and on all media - print and electronic. The National Library of Ireland is the Irish ISSN Centre and is the only institution that can supply an ISSN. There is an application process, and you must satisfy certain conditions. Apply for an ISSN. All of the journals publish through Arrow@TUDublin have ISSNs.