Glossary - Seagate STD124000N Product Manual

Glossary

Product Manual
absolute frame number (AFN). A sequence number encoded in the frame.
access point. Beginning of a sequence of compressed records at which point
codewords to a decompression algorithm must start—whether or not the required
data is at the beginning of the sequence.
algorithm. A set of rules for transforming the logical representation of data.
area ID. An identifier defining the area of the tape and specifying the types of frame
written.
azimuth. The angular deviation, in minutes of arc, of the mean flux transition line
from the line normal to the tape reference edge.
backup. Copy of a file or collection of files on fixed disc, diskette or tape. Ensures
against data loss.
beginning of media (BOM). Equal to the physical beginning of the tape, where the
leader tape is joined to the magnetic tape.
beginning of tape (BOT). Equal to the logical beginning of the tape.
bezel. Front panel of a drive.
bit. A single digit in the binary numbering system.
bit error rate. The number of errors divided by the total number of bits written or
read.
byte. A group of 8 binary bits operated on as a unit.
cartridge. An enclosure that contains magnetic tape wound on two coplanar hubs
and driven by an external drive.
channel bit. A bit after 8–10 transformation.
codeword. A word that is generated by a processing algorithm. The number of bits
in a codeword is variable.
compression ratio. The ratio that compares the amount of uncompressed data to
the amount of compressed data. It is obtained by dividing the size of the
uncompressed data by the size of the compressed data.
crosstalk. Signals from adjacent tracks that interfere with signals from another
track.
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