An archival collection contains those records for a person or organization which are no longer required for current use but have been selected for permanent preservation because of their evidential or informational value. It can also be the place (building / room / storage area) where archival material is kept.
An archival collection contains, principally, unpublished materials like diaries, personal photos, business records, etc., that are not necessarily created for public sale and consumption.
A library contains published materials that were created for public sale and consumption, like popular books and recordings you find at retail stores.
This is the order in which records and archives were kept when in active use.
The principle of original order requires that the original order be preserved or reconstructed, unless it is absolutely clear that there was no original order and that the records had been accumulated haphazardly.
This is the office or person or origin of records, i.e. the entity which created or accumulated and used the records in the conduct of business or personal life.
The authenticity and security of archival material is often tied to the the chain of custody, which involves the identifying and documenting the provenance of records.
In archival theory, the principle of provenance requires that the archives of an organization or person not be mixed or combined with the archives of another.
Adapted from Keeping Archives, c. 1987.