ORCID, which stands for Open Researcher and Contributor ID, is a free, unique, persistent identifier (PID) for individuals. ORCID is a non-profit organization created by the larger research community in an effort to support open science. ORCIDs help disambiguate and identify individual researchers and their scholarly output like publications, datasets, software, and more. With an ORCID, researchers can be connected to all their research across disciplines, institutions, and over time.
Your ORCID, or sometimes referred to as an ORCID iD, is an https URI with a 16-digit number that is randomly assigned by the system upon registration and should be expressed/presented as a full URL (not just the number). When talking about ORCID, oftentimes people are referring to both the ID number and the record (sometimes called a profile) that stores automatic links to all your research, and links all your research with you.