meljun cortes computer information processing chapter 5 with notes

7/31/2019 MELJUN CORTES Computer Information Processing Chapter 5 With Notes

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CCT101: Chapter 5

Storage


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OBJECTIVESOBJECTIVES

Differentiate between storage and memory

Identify various types of storage media and storage devices

Explain how data is stored on a floppy disk

Understand how to care for a floppy disk

List the advantages of using disks

Explain how data is stored on compact discs

Differentiate between CD-ROMs and DVD-ROMs

Identify uses of tapes, PC Cards, smart cards, microfilm, and

microfiche


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MEMORY VERSUS STORAGEMEMORY VERSUS STORAGE

Memory

Holds data and instructions while they are being processed by

the CPU

Volatile Nonvolatile


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Storage

Also called secondary storage, auxiliary storage, or mass

storage

Holds items such as data, instructions, and information for futureuse

Nonvolatile


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STORAGE MEDIUM (MEDIA) VERSUS

STORAGE DEVICES

STORAGE MEDIUM (MEDIA) VERSUS

STORAGE DEVICES Storage medium (media)

Physical material on which items are kept

Disk

Storage devices Mechanism used to record and retrieve items to and from a

storage medium


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Storage devices

Reading

Writing

Access time Minimum time it takes the device to locate a single item on a disk

Capacity


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FLOPPY DISKSFLOPPY DISKS

Portable

Inexpensive

3.5-inch disks

Used on many types of computers


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Characteristics of a Floppy Disk

Magnetic media

Uses magnetic patterns to store items

Formatting: preparing a floppy disk for use Track

Sector

Write-protect notch


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Floppy disk drive (FDD)

Can read or write a floppy disk

How a floppy disk drive works

Shutter Read/write head


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Care for Floppy Disks

Can last seven years

Avoid heat, cold, magnetic fields, dust, smoke, and salt air


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High-Capacity Floppy Disks

100 MB or greater capacity

Store large files such as graphics, audio, or video

Used for backups Zip drive


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HARD DISKSHARD DISKS

Primary media for storing software programs and files

4 to 50 GB capacity

Fixed disks in a personal computer


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Removable Hard Disks

Disk is enclosed in a plastic case

Easily transported


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Maintaining Data Stored on a Hard Disk

Preventive maintenance

Defragmentation

Scanning for errors


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COMPACT DISCSCOMPACT DISCS

Used to distribute software packages Stores items such as data, instructions, and information

Uses microscopic pits (indentations) and land (flat areas) in the

middle layer of the disc

A high-powered laser light creates the pits A lower-powered laser light reads items from the CD by

reflecting light through the bottom of the disc

The reflected light is converted into a series of bits

Land causes light to reflect (1s) Pits absorb the light (0s)

Stores items in spiraling tracks


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COMPACT DISCSCOMPACT DISCS

CD-ROM vs. DVD-ROM

Most computers have CD-ROM or DVD-ROM drive

Use jewel case to protect


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CD-ROMsCD-ROMs

Compact disc read-only memory

Can contain text, graphics, and video as well as sound

Cannot be erased or modified

Use CD-ROM drive or CD-ROM player to read

Holds about 700 MB

Used to distribute software


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CD-ROMsCD-ROMs

CD-ROM drive speed

Data transfer rate

The time it takes the drive to transmit data

Single-speed has a rate of 150 KB per second Current drives from 16X to 40X


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CD-ROMsCD-ROMs

CD-ROM variations

Multisession

Additional data, instructions, and information can be written to the

disc at a later time

Single-session

PhotoCD

Contains digital photographic images

CD-R (compact disc-recordable)

CD-RW (compact disc-rewritable)


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CD-ROMsCD-ROMs

DVD-ROMs

Digital video disc-ROM

Can hold much more data than CD-ROMs

4.7 GB to 17 GB

Higher quality than CD-ROMs

Often used for video

DVD variations

Digital movies and audio

Recordable Rewritable


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TAPESTAPES

Ribbon with a magnetic coating

Sequential access

Tape drive reads tapes

External tape drive


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PC CARDSPC CARDS

Thin, credit card-sized device that fits into a PC Card

expansion slot

Add storage, memory, communications, and sound

capabilities Used on laptops and portable computers

3 types

Type I and II used to add memory and communications

Type III used for hard disks


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OTHER TYPES OF STORAGEOTHER TYPES OF STORAGE

Smart Cards

Similar in size to credit card or ATM card

Has an embedded microprocessor

Intelligent smart card Memory card

Prepaid smart cards

Electronic money


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OTHER TYPES OF STORAGEOTHER TYPES OF STORAGE

Microfilm and Microfiche

Stores microscopic images of documents on roll or

sheet film

Microfilm

100 to 215-foot roll of film

Microfiche

Sheet of film usually about four inches by six inches

Often used by libraries and banks due to length oflife

meljun cortes computer information processing chapter 5 with notes

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