DOIs include a prefix (prefixes always start with 10.) and a suffix, separated by a forward slash (/). Prefacing the DOI with doi.org/ will turn it into an actionable link, for example, https://doi.org/10.1109/5.771073. Clicking that link will ‘resolve’ it, i.e. redirect to the latest information about the object it identifies, even if the object changes or moves.