Archives are the documents created, received, and accumulated by a person or organization in the course of the conduct of affairs, and preserved because of their continuing value. Records from an office or administrative unit are classified as a record group, and the records of an individual or family are classified as personal papers or manuscript collection. Archival records are arranged to represent their different levels of hierarchical control, as well as their creation, use, and storage. The basic units of archival control are as follows: record group or personal papers collection, subgroup, series, subseries, folder, and item. Within each group of records, some or all of the above levels of control will be present, the most prevalent record unit being the record series.