A system stores a snapshot and an associated data structure or index to storage media to create a secondary copy of a volume of data. In some cases, the associated index includes application specific data about a file system or other application that created the data to identify the location of the data. The associated index may include three entries, and may be used to facilitate the recovery of data via the snapshot. The snapshot may be used by ancillary applications to perform various functions, such as content indexing, data classification, deduplication, e-discovery, and other functions.