1、Chapter 8,Secondary Storage,8-2,Competencies (Page 1 of 2),Distinguish between primary and secondary storage Describe the traditional floppy disk and compare it to high capacity floppy disks Compare internal hard disks, hard-disk cartridges, and hard-disk packs,Page 218,8-3,Competencies (Page 2 of 2
2、),Describe ways to improve hard-disk operations, including disk caching, redundant arrays of inexpensive disks, and data compression and decompression Discuss the different types of optical disks Describe solid-state storage, Internet drives, and magnetic tape Discuss mass storage and mass storage d
3、evices,Page 218,8-4,Introduction,Data storage has expanded from text and numeric files to include digital music files, photographic files, video files, and much more. These new types of files require secondary storage devices with much greater capacity than floppy disks. In this chapter, you will le
4、arn about the many types of secondary storage devices including their capabilities and limitations.,Page 219,8-5,Storage,Primary storage Volatile storage Temporary storage,Secondary storage Nonvolatile storage Permanent storage Secondary storage characteristics Media Capacity Storage devices Access
5、speed,RAM,Page 220,8-6,Secondary Storage Devices,Most desktop microcomputer systems have floppy disks, hard disks, and optical disk drives Are used to save, back up, and transport data files and programs,Page 220,8-7,Floppy Disks,Portable or removable storage media Typically used to store and transf
6、er small word processing, spreadsheet, and other types of files Floppy disk drives (FDD) Store data and programs Retrieves data by reading electromagnetic charges Also called flexible disks and floppies,Page 220,8-8,Traditional Floppy Disk,Most common type is 2HD “two-sided, high-density” Attributes
7、 Shutter Labels Write-protection notch Tracks Sectors,Page 221,8-9,High Capacity Floppy Disks,Known as a floppy-disk cartridge Require special disk drives Most widely used is the Zip disk 100 MB, 250 MB or 750 MB capacity Used to store multimedia, database, large text, and spreadsheet files,Page 221
8、,8-10,Hard Disks,Use thicker, metallic platters for storage Faster than a floppy diskette Large capacity Sensitive instruments There are three types of hard disks: Internal Hard Disk Hard-disk cartridge Hard-disk pack Performance Enhancements,Page 221,8-11,Materials that Cause a Head Crash,Head cras
9、h is a disaster for a hard disk,Page 222,Return,8-12,Internal Hard Disk,Located inside system unit Designated as the C drive Advantages over floppies Capacity Access speed,Page 222,Return,8-13,Hard-Disk Cartridges,Removable hard disks Used to complement internal hard disk Capacities of 20 to 500 GB
10、Iomega is one of the most widely used,PC Card Hard Disks,Page 223,Hard-disk cartridge,Return,8-14,Hard-Disk Packs,Removable hard disk Massive storage capacity Common in mainframes Are utilized by banks and credit card companies,Page 224,Return,8-15,Performance Enhancements,Disk caching Redundant arr
11、ays of inexpensive disks (RAID) File compression and decompression,Page 225,8-16,Optical Disks,Hold over 50 gigabytes of data Attributes Lands PitsThree types Compact Disc (CD) Digital Versatile Disc (DVD) Hi-Def Disc,Page 226,8-17,Compact Disc,Optical format From 650 MB to 1 GB capacity Rotation sp
12、eeds vary Three basic types Read only: CD-ROM Write once: CD-R Rewriteable: CD-RW,Page 226,Return,8-18,Digital Versatile Disc,Digital Versatile Disc or Digital Video Disc (DVD) Similar to CDs, but can store more data Three basic types Read only: DVD-ROM Write once: DVD+R; DVD-R Rewritable: DVD+RW; D
13、VD-RW; DVD-RAM,Page 226,Return,8-19,High-Definition Disc,Next generation of optical disc Far greater capacity than DVDs Three basic types Read only Write once Rewriteable Two competing high definition formats HD DVD Blu-Ray,Page 227,8-20,Other Types of Secondary Storage,Solid-state storage Internet
14、hard drives Magnetic tape,Page 229,8-21,Ipods and Music From The Internet,The Internet can be used as a medium to locate and play music A user can create compact discs, or transfer music to a portable player Requirements Software Hardware Internet,Page 230,8-22,Solid-State Storage,Flash memory cards
15、 Widely used in notebook computers Used to record MP3 music filesUSB drives Key ring flash memory devices or flash drives Connects to a USB port,Page 232,Return,Key ring flash memory,Flash memory card,8-23,Internet Hard Drives,Known as i-drive or online storage Low cost and can access information fr
16、om any location using the Internet Oriented to either businesses or individuals,Page 232,Return,8-24,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 mainfram
17、es and microcomputers,Page 232,8-25,Mass Storage Devices,Mass storage refers to the tremendous amount of secondary storage required by large organizations Mass storage devices are specialized high-capacity secondary storage devices Enterprise storage system promotes efficient and safe use of data ac
18、ross networks within organizations,Page 233,8-26,Careers In IT,Software engineers analyze users needs and create application software General employer requirements Bachelors degree in computer science Extensive knowledge of computers and technology Good communication and analytical skills Software e
19、ngineers can expect to earn an annual salary of $53K to $88K,Page 234,8-27,A Look to the Future Your Entire Life Recorded on a Single Disk,Future secondary storage disks could eventually store one terabyte Experiments with three dimensional storing Video of an entire life Technology is being used to
20、 rapidly scan photos and videos,Page 235,8-28,Discussion Questions (Page 1 of 2),Discuss the traditional and high-capacity floppy disks. What are the three types of hard disks? Describe three ways to improve hard disk performance. What are the two most common optical disk formats? What is hi def? Describe the basic types for each format.,Page 242,8-29,Discussion Questions (Page 2 of 2),Discuss solid-state storage, Internet hard drives, and magnetic tape. What are the advantages and disadvantages of each? Discuss mass storage, enterprise storage systems, and mass storage devices.,Page 242,
