Object Identifier (OID)
A specialized formatted number that is registered with an internationally recognized standards organization. The unique alphanumeric/numeric identifier registered under the ISO registration standard to reference a specific object or object class. In the federal government PKI they are used to uniquely identify each of the four policies and cryptographic algorithms supported.
See NIST SP 800-32 for more information.
A globally unique identifier of a data object as defined in ISO/IEC 8824-2.
See NIST SP 800-73-4 under Object Identifier for more information.