Hierarchical Storage Management is a technology which has been available for over 15 years in the mainframe environment.  The Seagate Software HSM product was the first product to incorporate HSM technology and storage management technology for the PC/LAN environment.  An HSM system is a data storage management system.  Such a system is designed to automate the storage and retrieval of data on a variety of different types of devices.  These devices are arranged in a descending hierarchy according to storage cost and performance; and they can include hard disks, optical jukeboxes and tape autoloaders.

By utilizing HSM technology on a network, a storage management system can match the activity level of the HSM-managed data with the cost and performance of the particular device upon which that data is stored.  The most active files are left on fast-access, relatively expensive, daily-use network servers and systems.  Less active files are moved to slower-access, less expensive optical and/or tape devices.

A Hierarchical Storage Management (HSM) system manages the storage of network data so that active and inactive files are automatically separated and directed to the most cost-effective storage medium.  Files stored within the HSM device hierarchy are considered on-line, and can be returned to their original location in response to any "file open" request at any time.