Transcript Document

8
SECONDARY
STORAGE
8-2
Competencies
Distinguish between primary & secondary
storage
Discuss the different types of storage media
Describe the traditional floppy disk and the high
capacity floppy disks
Describe various types of hard disk devices
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8-3
Competencies cont.
Describe ways to improve hard-disk operations
Describe the different types of optical disks
Describe other kinds of secondary storage
devices
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8-4
Storage
Primary storage
Volatile
Temporary
Secondary storage
Nonvolatile
Permanent
Secondary storage
characteristics
Media
Capacity
Storage devices
Access speed
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8-5
Secondary Storage Devices
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8-6
Floppy Disks
Diskettes
Floppies
Portable storage
media
Floppy disk drives
(FDD)
Traditional Floppy
Disk
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8-7
Traditional Floppy Diskette
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8-8
Types of Floppies
High capacity
Known as a floppy-disk cartridge
Require special disk drives
Three well known types
Zip disks
HiFD disks
SuperDisks
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8-9
Hard Disks
Use thicker, metallic platters for storage
Faster than a floppy diskette
Large capacity
Sensitive instruments
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8-10
Materials that Cause a Head Crash
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8-11
Internal Hard Disk
Located inside system unit
Known as a fixed disk
Designated as the C drive
Advantages over floppies
Access speed
Capacity
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8-12
Hard-Disk Cartridges
Removable hard disks
Used to complement
internal hard disk
Capacities of 10 to 20
GB
PC Card Hard Disks
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8-13
Hard-Disk Packs
Removable
Massive storage capacity
Common in mainframes
Resembles stack of vinyl records
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8-14
Hard-Disk Pack
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8-15
Performance Enhancements
Disk caching
Redundant arrays of
inexpensive disks (RAID)
File compression
and decompression
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8-16
Optical Disks
Compact
Permanent storage
Laser beams reflect off pits
Two common types
CD
DVD
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8-17
Compact Disc
Optical format
From 650 MB to 1 GB capacity
Rotation speeds vary
Types
Read only: CD-ROM
Write once: CD-R
Rewriteable: CD-RW
Picture CDs and Photo CDs
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8-18
Digital Versatile Disc
Digital Versatile Disk or Digital Video Disk
(DVD)
Similar to CDs, but can store more data
Types
Read only
Write once
Rewritable
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8-19
DataPlay
Optical disk
Write once format
Quarter size
500 MB capacity
Holds 5 hours of CD-quality
sound
Use for storing and playing
music files
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8-20
Other Types of Secondary Storage
Solid-state storage
Internet hard drives
Magnetic tape
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8-21
Solid-State Storage
Flash memory cards
Widely used in notebook computers
Used to record MP3 music files
Key chain hard drives
Key chain flash memory
devices
Connects to a USB port
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8-22
Internet Hard Drives
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8-23
Magnetic Tape
External storage
Provides sequential access
Information stored in sequence
Slower than disks which provide
direct access
Magnetic tape streamers or tape
cartridges used by both
mainframes and
microcomputers
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8-24
A Look to the Future
Blu-Ray Technology
New standard in storage
Blu-Ray
New disks use blue laser light instead of the red laser
light used in traditional CD players
Disks may ultimately hold
Over 30GB on one-sided disks
Over 50GB on two-sided disks
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8-25
Key Terms
1.44 MB 31/2-inch disk
(211)
2HD (211)
access time (210)
C drive (213)
capacity (210)
CD (compact disc) (216)
CD burner (216)
CD-R (CD-recordable)
(216)
CD-ROM (compact discread only memory) (216)
CD-RW (compact disc
rewritable) (217)
DataPlay (220)
density (211)
direct access (221)
disk caching (213)
Diskette (210)
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8-26
Key Terms
disk (210)
DVD (digital versatile
disc or digital video disc)
(217)
DVD-RW or DVD+RW
(DVD rewritable) (217)
DVD-R or DVD+R
(DVD recordable) (217)
DVD-RAM (DVDrandom-access memory)
(217)
DVD player (217)
DVD-ROM (digital
versatile disc-read only
memory) (217)
Erasable optical disk
(217)
file compression (215)
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8-27
Key Terms
file decompression (215)
fixed disk (212)
flash memory card (221)
flexible disk (211)
floppies (211)
floppy disk (210)
floppy disk drive (FDD)
(210)
Floppy-disk cartridge
(211)
hard disk (212)
hard-disk cartridge (213)
hard-disk pack (214)
head crash (212)
HiFD disk (212)
high capacity floppy disk
(211)
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8-28
Key Terms
i-drive (221)
internal hard disk (212)
Internet hard drive (221)
jewel box (216)
key chain hard drives
(221)
label (211)
land (216)
magnetic tape (222)
magnetic tape reel (222)
magnetic tape streamer
(222)
media (210)
medium (210)
multiread (217)
multisession (217)
nonvolatile storage (210)
online storage (221)
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8-29
Key Terms
optical disk (216)
optical disk drive (216)
PC Card hard disk (214)
Photo CD (217)
Picture CD (217)
pit (216)
platters (212)
primary storage (210)
reading (210)
redundant arrays of
inexpensive disks
(RAID) (215)
removable hard disk
(213)
rotational speed (216)
secondary storage (210)
secondary storage device
(210)
sector (211)
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8-30
Key Terms
sequential access (221)
shutter (211)
single-session (217)
solid-state storage (220)
storage devices (210)
SuperDisk (212)
tape cartridge (222)
track (211)
volatile storage (210)
write-protection notch
(211)
writing (210)
Zip disk (211)
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8-31
FAQs
What is the difference between primary storage
and secondary storage?
What kinds of floppy disks are available?
What is the C drive of a computer?
When would I use a hard-disk cartridge?
What is the difference between a CD and a
DVD?
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8-32
Discussion Questions
Discuss three ways to improve the performance
of hard disks.
Describe the different types of compact discs.
Describe the different types of DVDs.
What are the advantages and disadvantages of
using an Internet hard drive?
Describe solid state technology. Discuss the
many uses for key chain flash memory devices.
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