Ensuring the findability of research data is crucial for the reusability of the data. An important step towards making data retrievable/findable is the assignment of so-called persistent identifiers (PID), which globally ensure the unique and permanent identification of a digital resource. They permanently refer to a specific content (e.g. data set) and link the associated metadata to the actual data set. A web link can change, a PID always remains the same. There are two types of PIDs:

DOIs serve as crucial tools for uniquely identifying and accessing digital resources. They are primarily assigned by authoritative bodies like DataCite, which ensure their official registration and management. Through the allocation of DOIs, research data and documents gain a distinctive identity. Moreover, DOIs enable linking between metadata and research data. This linkage facilitates effective data management and citation practices, making it easier for researchers to acknowledge and reference specific data in their work. Additionally, other identifiers like URNs (Uniform Resource Names) contribute to this ecosystem by providing a standardised nomenclature for digital resources. Meanwhile, identifiers such as ORCID, ResearcherID, and ROR establish clear and unambiguous scientific identities for individuals and organisations, further enhancing the accuracy and traceability of scholarly contributions. Repositories and journals automatically assign corresponding identifiers for the data/contributions submitted. If you also have a personal identifier (such as ORCID), your work can be automatically linked to your profile.