Quantum DLT 2000 Handbook page 197

G
Gigabyte (GB). A unit of measure consisting of one billion bytes
(one thousand megabytes).
H
Half Height. Standard drive size equivalent to half the vertical
space of a 5.25-inch drive.
Hard Error. A data error that persists when the tape is reread,
usually caused by defects in the physical surface.
Head. The tiny electromagnetic coil and metal pole used to create
and read back the magnetic patterns on the tape. Also known as
the read/write head.
Head Life. The length of time a tape drive head will function
without replacement or repair, usually measured in hours of use.
Helical Scan. Helical Scan technology drives employ a recording
style in which data tracks are written at an angle relative to the
edge of the tape rather than in a linear serpentine style of
DLTtape.
Hierarchical Storage Management (HSM). A storage system that
migrates the least-accessed data to secondary storage. The primary
purpose is to ease the management of data while reducing over-all
cost by storing this data on more cost-effective media like DLTtape
cartridges.
QUANTUM DLTtape HANDBOOK G.9