From an ORCID (Open Researcher and Contributor ID) Blog Post:
A number of organizations and individuals have been asking: what does an ORCID identifier look like? The ORCID ID is a 16-digit number that is compatible with the ISO Standard (ISO 27729). ORCID IDs will be randomly assigned by the ORCID Registry and will be expressed as a URI. An example ORCID identifier would have the following structure: http://orcid.org/0000-0002-3843-3472. Individuals will be able to register for an ORCID identifier at launch in October.
Learn More About the Structure of an ORCID Identifer
ORCID aims to solve the name ambiguity problem in scholarly communications by creating a registry of persistent unique identifiers for individual researchers and an open and transparent linking mechanism between ORCID, other ID schemes, and research objects such as publications, grants, and patents.
Hat Tip: Knowledgespeak