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8-2 Competencies

Distinguish between primary & secondary storage SECONDARY Discuss the different types of storage media STORAGE Describe the traditional floppy disk and the high 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 Secondary storage devices characteristics Media Capacity Storage devices Access speed

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8-5 8-6 Secondary Storage Devices 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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8-7 8-8 Traditional Floppy Disks Types of Floppies

High capacity Traditional Known as a floppy-disk cartridge Floppies Require special disk drives Diskettes Three well known types Portable storage Zip disks media HiFD disks Floppy disk drives Traditional Floppy Diskette SuperDisks (FDD)

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8-9 8-10 Hard Disks Hard-Disk Cartridges

Use thicker, metallic platters for storage Removable hard disks Internal (fixed) or external Faster access speed than a floppy diskette Used to complement internal hard disk Direct or random access to data Large capacity Capacities of 10 to 20 GB Sensitive instruments PC Card Hard Disks

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8-11 8-12 Hard-Disk Packs Performance Enhancements

Removable Disk caching Massive storage capacity Common in mainframes Redundant arrays of Resembles stack of vinyl records inexpensive disks (RAID)

File compression and decompression

Defragmentation

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8-13 8-14 Optical Disks Compact Disc

Compact Optical format Permanent storage From 650 MB to 1 GB capacity Laser beams reflect off pits Rotation speeds vary Two common types Types CD Read only: CD-ROM DVD Write once: CD-R Rewriteable: CD-RW Picture CDs and Photo CDs

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8-15 8-16 Digital Versatile Disc Blu-Ray Technology

Digital Versatile Disk or Digital Video Disk New standard in storage (DVD) Blu-Ray Similar to CDs, but can store more data New disks use blue laser light instead of the red laser Types light used in traditional CD players Read only: DVD-ROM Disks may ultimately hold Over 30GB on one-sided disks Write once: DVD-R Over 50GB on two-sided disks Rewritable: DVD-RW

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8-17 8-18 DataPlay Solid-State Storage

Optical disk Flash memory cards Write once format Widely used in notebook computers Quarter size Used to record MP3 music files 500 MB capacity Expanded digital camera use Holds 5 hours of CD-quality sound Key chain hard drives Use for storing and playing Key chain flash memory music files devices Connects to a USB port

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8-19 8-20 Internet Hard Drives FAQs

What is the difference between primary storage and secondary storage? What kind of data access do floppy and hard drives use ? 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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8-21 8-22 Discussion Questions Participation Question

Discuss three ways to improve the performance Optical disks that can be written on only once are of hard disks. called identified as ____ . Describe the different types of compact discs. Describe the different types of DVDs. A. CD-ROM What are the advantages and disadvantages of B. CD-R using an Internet hard drive? C. CD-RW Describe solid state technology. Discuss the D. CD-DVD many uses for key chain flash memory devices. E. CD-W

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