How is an archivist different from other jobs?

There are three other jobs similar to archival work, yet all are different and unique in their own way.

Records Manager-
Records Managers mainly deal with current records from their creation to their disposal (disposal either for desctruction or transfer to an archive).
Librarian-
Archivists differ from librarians in several ways one is that archivists mainly work with original/unpublished records where there is limited access. Librarians have published material most likely in open stacks.
Curator-
"Curators usually handle objects found in cultural, biological, or historical collections, such as sculptures, textiles, and paintings, while archivists mainly handle valuable records, documents, or objects that are retrieved because they originally accompanied and relate specifically to the document"- From the Occupational Handbook [wp].