EMC DL3D 1500 Administrator's Manual page 229

Glossary
B
Beginning of tape
The first point on the tape that can be accessed by the drive. Also
referred to as the beginning of media (BOM).
Bit
The basic unit of data in a binary numbering system (binary digit),
represented by a 0 or a 1. Eight bits equals one byte.
Byte
The basic unit of computer memory which is large enough to hold
one character.
C
Class A digital device Class A equipment is intended for Commercial installation.
Compress A process of removing fine-grained redundancy from data prior to
storing or transmitting it. The granularity may vary, but generally
compression deals with redundancy in grains of a few bytes.
D
De-duplicate A process of removing coarse-grained redundancy from data prior to
storing or transmitting it. The granularity may vary, but generally
de-duplication deals with redundancy in grains of several kilobytes.
Direct access
A physical tape volume may be accessed directly, that is, inserted into
a virtual tape drive and accessed through that virtual tape drive by
the user. Direct access is an aspect of the DL3D 1500/3000 integrated
path-to-tape feature.
EMC DL3D 1500 and DL3D 3000 Administrator's Guide 229