Digital object identifiers (DOIs) have become essential tools in academic publishing for linking and identifying digital objects. This review examines the structure and assignment process of DOIs, shedding light on their critical importance in scholarly communication. DOIs consist of a unique alphanumeric string, including a prefix and a suffix, which serves as a persistent link to digital objects. By providing a standardized identifier, DOIs enhance the discoverability, accessibility, and referencing of various digital objects, including journal articles. The DOI also plays a crucial role in article promotion. With a DOI, authors, publishers, and researchers can effectively share and promote their articles, facilitating their discoverability in academic and research communities. However, challenges may arise with DOIs, such as non-functional links. This review provides troubleshooting tips for resolving such issues, including checking for typographical errors, validating the source, and seeking assistance from the DOI registration agency or the publisher.