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Distinguish between primary & secondary storage
Discuss the different types of storage media
Floppy disk, hard disk and optical disk
Describe the traditional floppy disk and the high capacity floppy disks
Describe various types of hard disk devices
Internal HD , HD cartridge and HD packs
.
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Describe ways to improve hard-disk operations
Disk caching, data compression
Describe the different types of optical disks
Describe other kinds of secondary storage devices .
Solid state storage, internet drives and magnetic tape
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Primary storage
Volatile
Temporary
It loses all of its contents when power to the system unit is shut off.
Secondary storage
Nonvolatile
Permanent
Writing : is the process of saving information.
Reading: is the process of accessing information.
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Secondary storage characteristics
 Media ( actual physical material that holds the data and programs, Example: CD).

Capacity ( measured how much a particular storage medium can hold)
 Storage devices
(are hardware that reads data and program from storage media)

Access speed ( measures the amount of time required by storage device to retrieve data and program).
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Diskettes
Flexible disk and Floppies
The plastic disk inside the diskette cover is flexible
Traditional Floppy
Disk
Portable storage media

Floppy disk drives (FDD)
Store data and programs by altering the electromagnetic charges on the
Disk surface to represent ones and zeroes.
 Characters are represented by positive + and – charges using ASCII code.
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3.5 inch, 1.44 MB
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High capacity
Known as a floppy-disk cartridge
Require special disk drives
Three well known types
Zip disks (Iomega)
100MB, 250MB, 750MB
HiFD disks (Sony)
200MB, 720MB, read and store data on 1.44MB disk
SuperDisks (Imation)
240MB, 120MB
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Zip disks (Iomega)
HiFD disks
(Sony)
SuperDisks (Imation)
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Use thicker, metallic platters for storage
Faster than a floppy diskette
Large capacity
Sensitive instruments
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A head crash occurs when a read/write head makes contact with the hard disk’s surface or with particles on its surface.
Three types of HD

Internal H.D
 H.D Cartridge.

H.D Pack.
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Located inside system unit
Known as a fixed disk
Designated as the C drive
Advantages over floppies
Access speed
Capacity
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Removable hard disks
Used to complement internal hard disk
Capacities of 10 to 20
GB
PC Card Hard Disks
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Peerless Disk
PC Card Hard Disks
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Removable
Massive storage capacity
Common in mainframes
Used in Banks and credit cards companies.
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Disk caching
Redundant arrays of inexpensive disks (RAID) expanding external storage several hard disk drives are connected to one another.
File compression and decompression
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Compact
Permanent storage
Optical disk use reflected light.
The 1s and 0s are represented by flat areas called lands and bumpy areas called pits.
Two common types
CD ( 650 MB to 1GB)
DVD ( 4.7 GB to 17 GB)
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Optical format
From 650 MB to 1 GB capacity
Rotation speeds vary
It determines how fast data can be transferred from the CD
24X or 24- speed CD drive can transfer 3.6 MB per second.
Types
Read only: CD-ROM
Write once: CD-R
Rewriteable: CD-RW
Picture CDs and Photo CDs
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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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Optical disk
Write once format
Quarter size
500 MB capacity
Holds 5 hours of CD-quality sound
Use for storing and playing music files
Data play format ( search for it)
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Solid-state storage
Internet hard drives
Magnetic tape
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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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Special service sites on the WEB provide users
With storage
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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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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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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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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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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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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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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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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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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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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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