Archives can hold both published and unpublished materials, and those materials can be in any format. Some examples are manuscripts, letters, photographs, moving image and sound materials, artwork, books, diaries, artifacts, and the digital equivalents of all of these things. Materials in an archives are often unique, specialized, or rare objects, meaning very few of them exist in the world, or they are the only ones of their kind.
Archivists are in charge of an archives basic organization based on provenance and original order.
Since materials in archival collections are unique, the people (archivists) in charge of caring for those materials strive to preserve them for use today, and for future generations of researchers. Archives have specific guidelines for how people may use collections (which will be discussed later in this guide) to protect the materials from physical damage and theft, keeping them and their content accessible for posterity.