计算机专业英语影印版(Computing Essentials 2008)课后答案大全——第八单元Chapter 8 Secondary Storage

Key Terms Key Term Definition access speed (214) Measures the amount of time required by the storage device to retrieve data and programs. Blu-Ray (BD) (222) A different optical format than either the DVD or the HD DVD and have a capacity of 25 to 50 gigabytes, CD (compact disc) (220) One of the most widely used optical formats. CD-R (CD-recordable) (220) A CD that can be written to only once. CD-ROM (compact disc–read only memory) (220) A CD that cannot be written on or erased by the user. CD-ROM jukebox (228) Provide automatic access to a large collection or library of optical disks. CD-RW (compact disc rewritable) (221) A CD that can be written to many times. (See also erasable optical disc) cylinder (216) A part of a hard disk that runs through each track of a stack of platters. density (215) How tightly the bits (electromagnetic charges) can be packed next to one another on a diskette. direct access (226) The type of storage and retrieval system used by magnetic and optical discs. disk caching (219) A hard disk performance enhancement that improves processing by acting as a temporary high-speed holding area between a secondary storage device and the CPU. DVD (digital versatile disc or digital video disc) (221) a newer optical format that has replaced CDs as the standard; similar to CDs except that more data can be packed into the same amount of space. DVD player (221) DVD ROM drive DVD +R (DVD recordable) (221) A type of DVD write-once format DVD -R (DVD recordable) (221) A type of DVD write-once format DVD-RAM (DVD random-access memory) (221) A type of DVD rewriteable format DVD-ROM (DVD–read only memory) (221) A DVD format that the user cannot write to DVD-ROM jukebox (228) Provide automatic access to a large collection or library of optical disks. DVD +RW (DVD rewritable) (221) A type of DVD rewriteable format DVD -RW (DVD rewritable) (221) A type of DVD rewriteable format enterprise storage system (227) A type of system that large organizations use to promote efficient and safe use of data across the networks within their organizations. erasable optical disc (221) A CD that can be written to many times. (See also CD-RW (compact disc rewritable)) file compression (219) A hard disk performance enhancement that increases storage capacity by reducing the amount of space required to store data and programs. file decompression (219) Rebuilding a file that has been compressed file server (228) A dedicated computer with very large storage capacity that provides users access to fast storage and retrieval of data. flash memory card (223) Credit card–sized solid-state storage devices widely used in notebook computers. floppy disk (214) A portable or removable storage medium that uses flat circular pieces of Mylar plastic that have been coated with a magnetic material. floppy-disk cartridge (214, 215) Portable storage devices that are able to store more information, and are thicker than a diskette. (see also high capacity disk) floppy disk drive (FDD) (214) Stores data and programs by altering the electromagnetic charges on the disk’s surface to represent 1s and 0s hard disk (216) A device that saves files by altering the magnetic charges of the disk’s surface, has greater capacity than a diskette, and faster access time. hard-disk cartridge (217) Easy to remove cassettes whose capacity is only limited by the number of cartridges. hard-disk pack (218) Removable storage device used to store massive amounts of information. HD DVD (high-definition DVD) (222) This format is very similar to DVD except that its storage capacity is much greater. head crash (216) When a hard disk’s read/write head makes contact with the hard disk’s surface or with particles on its surface resulting in a catastrophic loss of data. hi def (high definition) (222) The next generation of optical disc high-capacity disk (215) Portable storage devices that are able to store more information, and are thicker than a diskette. (see also floppy disk cartridge) internal hard disk (216) A magnetic secondary storage device that is located inside the system unit. Internet hard drive (226) Special service sites on the Web provide users with storage. label (215) Usually on the front of a diskette and provides users with an area to write or document the contents of the disk. land (220) Flat areas that optical discs use to represent 1s and 0s. magnetic tape (226) Writes data and programs by altering the electromagnetic charges on a recording surface and uses a sequential access method to store and retrieve it. magnetic tape reel (227) Type of tape that was used by mainframes and is typically 1/2 inch wide and 11/2 miles long and provides massive storage capacity. magnetic tape streamer (227) The type of magnetic tape technology used by mainframes today. mass storage (227) The tremendous amount of secondary storage required by large organizations. mass storage devices (227) Specialized high-capacity secondary storage devices designed to meet storage requirements of large organizations. media (214) An actual physical material that holds data and programs. optical disc (220) A storage device that uses a laser beam to alter the surface of a plastic or metallic disc to represent data optical disc drive (220) A device with a laser that projects a tiny beam of light on a disc to reflect the light to determine a pit or land. organizational Internet storage (228) High-speed Internet connection to a dedicated remote organizational Internet drive site. PC Card hard disk (217) Credit card-size hard-disk cartridges available for notebook computers with typical capacities up to 5 gigabytes. pit (220) The bumpy areas that optical discs use to represent 1s and 0s. primary storage (214) RAM or memory, where data is stored before being processed. RAID system (228) A system that enhances organizational security by constantly making backup copies of files moving across the organization’s networks. redundant array of inexpensive disks (RAID) (219) improve performance by expanding external storage, improving access speed, and providing reliable storage. secondary storage (214) Provides permanent or nonvolatile storage secondary storage device (214) Hardware where data and programs can be retained after the computer has been shut off. (see also storage device) sector (215) A wedge-shaped sections of a track, part of how files are stored and organized on a flexible disk sequential access (226) The type of storage and retrieval system used by magnetic tape. shutter (215) Part of a diskette that slides to the side to expose the recording surface. software engineer (228) A computer professional who analyzes users’ needs and creates application software. solid-state storage (223) Storage devices have no moving parts. storage device (214) Hardware where data and programs can be retained after the computer has been shut off. (see also secondary storage device) tape cartridge (227) The type of magnetic tape technology used by mainframes today tape library (228) A device that provides automatic access to data archived on a large collection or library of tapes. track (215) Rings of concentric circles without visible grooves, part of how files are stored and organized on a flexible disk USB drive (226) The size of a key chain; these hard drives connect to a computer’s USB port enabling a transfer of files; has a capacity of 2GB. write-protection notch (215) A slide on a diskette that opens and closes. When closed, files can be saved to the disk. When open, files cannot.     Crossword Puzzle Answers: Across Num. Clue Answer 5 Improves hard-disk performance by anticipating data needs. Disk caching 6 Web-based storage. Internet drive 7 Invisible wedge-shaped division of a track. Sector 8 Portable and removable storage device. Floppy 10 Runs through each track of a stack of platters. Cylinder 11 How tightly the bits can be packed next to each other. Density       Down Num. Clue Answer 1 Ring of concentric circles without visible grooves. Track 2 Grouped disk drives treated as one hard disk by the computer system. RAID 3 Measures the amount of time required to retrieve data. Access time 4 Represent 1s and 0s. Pits and lands 9 Disk with 500 times the storage as a standard floppy. Zip       Num Multiple Choice Answers Matching Answers 1 A G 2 A A 3 C J 4 A I 5 C D 6 A B 7 C H 8 D C 9 D F 10 C E       Open Ended Questions: 1. Discuss the traditional and high-capacity floppy disks. The traditional floppy disk is the 1.44 MB 31/2-inch disk. The most common type is labeled 2HD, which means “two-sided, high-density” and have a capacity of 1.44 MB. Floppy disks have a thin exterior jacket made of hard plastic to protect the flexible disk inside. High-capacity disks, also known as floppy-disk cartridges, are rapidly replacing the traditional floppy disk.  They are 31/2 inches in diameter, and are able to store more information, are thicker, and require special disk drives. 2. What are the three types of hard disks? Describe three ways to improve hard-disk performance. There are three types of hard disks: internal hard disk, hard-disk cartridge, and hard-disk pack. Three ways to improve the performance of hard disks are disk caching, redundant arrays of inexpensive disks, and file compression/decompression.  Disk caching improves processing by acting as a temporary high-speed holding area between a secondary storage device and the CPU.  Redundant arrays of inexpensive disks (RAID) improve performance by expanding external storage, improving access speed, and providing reliable storage.  File compression and file decompression increase storage capacity by reducing the amount of space required to store data and programs. 3. What are the two most common optical disc formats? What is hi def? Describe the basic types for each format. The two most common optical disc formats are CD and DVD.  The next generation of optical disc is called hi def (high definition), with a far greater capacity than DVDs.  CDs, DVDs, and hi def have three basic types: read only, write once, and rewriteable. 4. Discuss solid-state storage, Internet hard drives, and magnetic tape. What are the advantages and disadvantages of each? Solid-state storage devices have no moving parts.  While this type of storage is more expensive than the others, it is more reliable and requires less power. Internet hard drives are special service sites on the Web that provide users with storage.  Advantages of Internet hard drives include low cost and the flexibility to access information from any location using the Internet.  Disadvantages are access speed is slower because all information must travel across the Internet, and users are dependent on the availability and security procedures of the service site. Magnetic tape stores data and programs by altering the electromagnetic charges on a recording surface. One of the cheapest forms of secondary.  However, it uses sequential access methods so it is one of the slowest to access specific information.  Magnetic tape is an effective and commonly used tool for backing up data. 固态存储设备没有移动部件。而这种类型的存储更昂贵的比其他的,更可靠,需要更少的力量。网络硬盘是特殊服务网站,为用户提供存储。网络硬盘的优点包括:低成本、灵活地使用互联网从任何位置访问信息。缺点是访问速度慢,因为所有的信息都必须穿越互联网,和用户依赖于服务的可用性和安全程序的网站。磁带存储数据和程序通过改变电磁面的指控。最便宜的形式的中学之一。然而,它使用顺序存取方法,这是最慢的访问特定的信息。磁带是一种有效和常用工具备份数据 5. Discuss mass storage, enterprise storage systems, and mass storage devices. Mass storage refers to the tremendous amount of secondary storage required by large organizations.  Enterprise storage systems are systems that large organizations use to promote efficient and safe use of data across the networks within their organizations.    Mass storage devices are specialized high-capacity secondary storage devices designed to meet organizational demands for data. Focus Applying Technology Expanding Your Knowledge Writing About Technology Ethical     CD-R and Music Files Web Tools iPods and Music from the Internet How Music Is Downloaded from the Internet Internet Hard Drives   Software Tools iPod USB Storage File Compression   Writing Skills     Storage Trade-offs         Ethical focus 1. Writing About Technology exercise #1 CD-R and Music Files looks at the distribution of music on the Internet and the ethical problem of copying music that isn’t freely distributed.