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8-2 Competencies

Distinguish between primary & secondary storage SECONDARY Discuss the different types of storage media STORAGE Descr ibe th e tradi ti onal fl oppy di sk and th e hi gh capacity floppy disks Describe various types of hard disk devices

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8-3 8-4 Competencies cont. Storage

Describe ways to improve hard-disk operations Primary storage Secondary storage Describe the different types of optical disks Volatile Nonvolatile Temporary Permanent Describe other kinds of secondary storage Secondaryyg storage didevices characteristics Media Capacity Storage devices Access speed

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8-5 8-6 Secondary Storage Devices Traditional Floppy Disks

Traditional Floppies DiDiskettesskettes Portable storage media Traditional Floppy Floppy disk drives Diskette (FDD)

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8-7 8-8 Types of Floppies Hard Disks

High capacity Use thicker, metallic platters for storage Known as a floppy-disk cartridge Internal (fixed) or external Require special disk drives Faster access speed than a floppy diskette Three well known types Direct or random access to data Zip disks Large capacity HiFD disks Sensitive instruments SuperDisks

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8-9 8-10 Hard-Disk Cartridges Hard-Disk Packs

Removable Removable hard disks Massive storage capacity Used to complement Common in mainframes internal hard disk Resembles stack of vinyl records Capacities of 10 to 20 GB PC Card Hard Disks

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8-11 8-12 Performance Enhancements Optical Disks

Disk caching Compact Permanent storage Redundant arrays of inexpp()ensive disks (RAID) Laser beams reflect off pits Two common types File compression CD and decompression DVD

Defragmentation

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8-13 8-14 Compact Disc Digital Versatile Disc

Optical format Digital Versatile Disk or Digital Video Disk From 650 MB to 1 GB capacity (DVD) Rotation speeds vary Similar to CDs, but can store more data Types Types Read only: CD-ROM Read only: DVD-ROM Write once: CD-R Write once: DVD-R Rewriteable: CD-RW Rewritable: DVD-RW Picture CDs and Photo CDs

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8-15 8-16 DataPlay Other Types of Secondary Storage

Optical disk Solid-state storage Write once format Quarter size Internet hard drives 500 MB capacity Holds 5 hours of CD-quality Magnetic tape sound Use for storing and playing music files

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8-17 8-18 Magnetic Tape Solid-State Storage

External storage Flash memory cards Provides sequential access Widely used in notebook computers Information stored in sequence Used to record MP3 music files Slower th an di sk s whi ch provid e direct access Key chain hard drives Magnetic tape streamers or tape Key chain flash memory cartridges used by both devices mainframes and Connects to a USB port microcomputers

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8-19 8-20 Internet Hard Drives 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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8-21 8-22 FAQs Discussion Questions

What is the difference between primary storage Discuss three ways to improve the performance and secondary storage? of hard disks. What kind of data access do floppy and hard Describe the different types of compact discs. drives use ? Descr ibe th e diff erent types of DVD s. What is the C drive of a computer? What are the advantages and disadvantages of When would I use a hard-disk cartridge? using an Internet hard drive? What is the difference between a CD and a Describe solid state technology. Discuss the DVD? many uses for key chain flash memory devices.

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8-23 Participation Question

Optical disks that can be written on only once are called: A. CD-ROM B. CD-R C. CD-RW D. CD-DVD E. CD-W

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