翻译：
1、C++’s advantages include strong typing, operator overloading, and less emphasis on the preprocessor.
C++的优点包括强类型，运算符重载和较少地强调预处理器。
2、A program instruction or a piece of data is stored in a specific primary storage location called an address.
程序指令和数据是存储在主存中一个特殊的位置，称为地址空间
3、A high-level language is an artificial language with which we can write various instructions. This is possible not because computer processors are now so technologically advanced that they can ‘understand’ these langu ages. You should translate from programming languages into machine language which can be understood by the computer processors. Compilers can accomplish this task. This does mean that a high-level language program is not directly executable: it must be compiled to produce processor program, which is executable.
高级语言是一门人工的我们可以写入各种各样指令的语言。这是有可能的并不是因为计算机处理器现在有先进的技术可以懂得这些语言。你应该将编写好的程序语言转化为计算机处理器可以理解的机器语言。编写者可以完成这个任务。这就意味着高级语言程序不是直接执行的：它必须编写生成可以执行的处理器语言。
问答：（注意尽量用英文回答），都是课本上有的内容。
1、What are the consequences of Moore’s law? 1. The cost of a chip has remained virtually unchanged during this period of rapid growth in density. This mean that the cost of computer logic and memory circuitry has fallen at a dramatic rate .
2. Because logic and memory elements are placed closer together on more densely packed chips, the electrical path length is shortened, increasing operating speed .
3. The computer becomes smaller ,make it more convenient to place in a variety of environments.
4. The interconnections on the integrated circuit are much more reliable than solder connections. With more circuitry on each chip, there are fewer interchip connections.
2、What does C++ have that makes it a suitable language for developing object-oriented programs?
The answer is the class data type. It is C++’s class type ,built upon C’s struct type, that gives the language the ability to build objects .Also，C++ brings several additional features to object-oriented programming not included in other languages that simply make use of objects, C++’include strong typing, operator overloading, and less emphasis on the preprocessor. It is true that you can do object-oriented programming with other products and in other languages, but with C++ the benefits are outstanding. This is a language that was designed, not retrofitted, for object-oriented programming.
2014年上半学期计算机专业英语 期末考试试卷（A卷）答案 一、选择题 Ⅰ. Vocabulary(词汇)(30分) (一)．Translate the following words and expressions into Chinese(写出下列词组的汉语。)( 共10分，每题1分) 1. 操作系统 2. 需求分析 3. 网络安全 4. 数据结构 5. 决策支持系统 6. 关系数据库 7. 软件危机 8. 计算机病毒 9. 邮件附件 10．中央处理器（单元） (二)．Fill in the blanks with the corresponding English abbreviatio ns.(根据汉语写出相应的英语缩写。) (共10分，每题1分) 1．DBMS 2．TCP 3．MDI 4．OOP
5．ROM 6．VCD 7．CAD 8．SQL 9．USB 10．B2B （三） Match the following words and expressions in the left column with those similar in meaning in the right column.(将左列的词汇与右列相应的汉语匹配。)(10分，每空1分) 1． c 6. h 2． f 7．j 3． e 8. d 4．g 9. i 5． a 1 0. b Ⅱ. Comprehension(阅读理解) （一）
Fill in the blanks with suitable words or expressions from the lis t given below, and change the form where necessary. （从下面方框中选择合适的词或表达，以其适当的形式填空。）(10分, 每空2分) maintain disciplined requirements coding modified （二） Tell whether the following statements are true(T) or false(F) accord ing to the passage A.（根据上文的内容判断下列句子的正误）（10分,每题2分）1．F 2．T 3．F 4．T 5．F (三)、choose the best answer according to the passage B.(根据上文的内容选择正确的答案。（10分，每题2分） 1．B 2．A 3．D 4．B 5．C (四) Choose the best answer according to Passage C.（根据上文的内容选择正确的答案。10分，每题2分） 1．C 2. D 3. A 4. C 5. B Ⅲ.Translation.翻译(30分) (一) Translate the following sentences into Chinese.（将下列句子翻译成汉语。）（共20分，每题5分）
少工学结合创新教程....................... 计算机专业英语 2014年上半学期计算机专业英语 期末考试试卷（A卷）答案 一、选择题 I . Vocabulary（词汇）（30 分） （一）.Tran slate the follow ing words and expressi ons into Chin ese（ 汉语。）（共10分，每题1分） 1. 操作系统 2. 需求分析 3. 网络安全 4. 数据结构 5. 决策支持系统 6. 关系数据库 7. 软件危机 8. 计算机病毒 9. 邮件附件 10. 中央处理器（单元） （二）.Fill in the blanks with the corresponding English abbreviations.（ 写出相应的英语缩写。）（共10分，每题1分） 1 . DBMS 2. TCP 3. MDI 4. OOP 5. ROM 6. VCD 7 . CAD 8 . SQL 9 . USB 10. B2B （三） Match the following words and expressions in the left column with those similar in mea ning in the right colum n.（将左列的词汇与右列相应的汉语匹配。写出下列词组的 根据汉语）（10分，每空
1分） 1. c 6. h
1. 开发一个软件产品，开发过程分为五个步骤：需求分析和说明，设计，写代码，测试和维护。 2. 功能测试检验的是用有效的输入是否能够得到所期望的输出。+ 3. EDI指的是两个公司之间通过私有网络使用特定、结构化的格式电子交换商业信息。 4. 一些应用软件，例如Word,允许几个窗口同时在一个叫做MDI的模式下存在，你能够在 一个软件中打开多个文档。 （二）Tran slate the follow ing paragraph into Chi nese. （将下段文章翻译成汉语。）（共10分） 高级语言是一种人造语言，使用它我们可以写不同的指令。这成为可能不是因为计算机处理器如今是如此的技术先进以至于它们可以理解这些语言。你需要将这些语言翻译成计算机处理器能够理解的机器语言。编译器能够完成这项工作。这就意味着高级语言程序不是直接可项目1 3. e 8. d 4. g 9. i 5. a 10. b n . Comprehension（阅读理解） （一） Fill in the bla nks with suitable words or expressi ons from the list give n below ,and change the form where necessary. （从下面方框中选择合适的词或表达，以其适 当的形式填空。）（10分，每空2分） maintain discipli ned requireme nts codi ng modified （二）项目2 项目3 Tell whether the follow ing stateme nts are true（T） or false（F） accord ing to the passage A.（根据上文的内容判断下列句子的正误）（10分，每题2分）项目4 1 . F 2 . T 3 . F 4 . T 5 . F （三）、choose the best answer according to the passage B.（确的答案。（10分，每题2分） 1 . B 2 . A 3 . D 4 . B 5 . C （四）Choose the best answer according to Passage C. 案。10分，每题2分） 1 . C 根据上文的内容选择正 （根据上文的内容选择正确的答 项目5 2. D 3. A 项目6 4. C 5. B 川.Translation. 翻译（30 分） （一）Tran slate the followi ng senten ces in to Chin ese. 20分，每题5分）（将下列句子翻译成汉 语。 ） （共 项目7 项目8 项目9 项目10
第9单元电子商务 第一部分听力和对话 对话：使用在线支付服务保护消费者的隐私 (Henry非常兴奋地在一家网上书店中发现了自己期待已久的图书，但是当得知系统要 求通过账号支付时，他犹豫了。) Henry: 最近互联网上信用卡账号的公然欺骗无疑为我们敲响了警钟。在进行在线交易时，我们并不知道要把自己的信用卡账号告诉谁。 Mark: 也许你可以使用第三方支付服务来保证在线支付更简单、更安全。 Henry: 什么是第三方支付服务？ Sophie: 简单地说，在使用第三方支付服务时，你可以把自己的资金转移到一个在线账号中，然后从那个账号中进行支付。这样就不用把自己的真实信用卡或银号账户信息暴露在网络上了。 Henry: 这种方法听起来更安全。有哪些第三方支付服务可以方便地使用？ Mark:在美国最受欢迎的服务是eBay公司掌控的PayPal,但也有一些其他的服务，如https://www.doczj.com/doc/6311713.html, Payment等。以最简单的支付为例，例如在线拍卖或简单的网站销售，销售商只需要向买家提供他们的E-mail地址，而买家向销售商的PayPal账号进行适当的支付。Henry: 我明白了。 Sophie: 做出选择之后，建议你留意选择更加安全服务的一些细节。 Henry: 什么是更加安全服务的一些细节呢？ Sophie: 首先，阅读隐私政策，并确保自己同意其中的条款。如果不同意，可以继续选择其他的安全服务。此外，确认网站符合权威部门规定的特定的标准（查验同意的盖章）。这些的确都是非常重要但是有时被用户忽略的步骤。 Mark: 当使用第三方支付服务时，Henry,请记住千万不要回复来自第三方支付服务机构发送的要求确认如密码或其他私人身份识别信息等与账号细节相关的电子邮件。这些邮件很可能是身份盗窃骗局，如网络钓鱼。 Henry: 那么，怎样才能更安全地确认或处理我的账号细节呢？ Sophie: 如果需要确认或更新账号信息或者修改密码，我建议你可通过个人书签或者在浏览器中直接输入支付服务网站的URL来访问相应的网站。 Henry: 如何进一步确认卖家能够提供有效的支付服务？ Mark: 你可以通过查看卖家在几个月或更长的时间内是否为支付服务机构的有效成员来确定。有些网站还允许用户查看卖家的评价，虽然这些评价并不能作为保证，但是却是非常有用的信息。 Sophie: 切记，Henry,不要用自己的账号把资金转移到一个你不认识的人的账号里。这可能是一种高级的资金诈骗。还有，当你要购买一些诸如珠宝或者计算机等昂贵的物品时，尤其是在节假日或者商铺中售出的物品时，需要多加小心。 Henry: 好的。现在我对进行安全在线支付更加有信心了。非常感谢你们的见议。 练习
计算机英语期末考试试题 I. 单选题. (1*20) 1.A computer system includes both _________ and software. A.cable B.memories C.CPU D.hardware 2.The heart of the computer is _________ A.CPU B.BUS C.CAI D.DIV 3.Which is not input device used with microcomputers ? A.Keyboard B.Printer C.touch screen D.Mouse 4.Basically , a computer consists of four components : Central Processing Unit , _________, Input Device and Output Device. A.Memory B.Keyboard C.Monitor D.The Control Unit 5.A _________ is a small , hand-held object that is pushed around a desktop to move the cursor or pointer on the screen or to select choices from menu displayed on screen. A.keyboard B.mouse C.monitor D.printer 6.Which is "删除" in Chinese ? A.shift B.Control C.Insert D.Delete 7.__________ refers to the parts of the computer that you can see and touch. A. Software B. Hardware C. Hardship D. Instruction 8._________ is used to communicate with another computer over telephone lines A. keyboard B .modem C. printer D. Mouse 9.__________is a device that enables the computer to handle sounds. A. network card B. video card C. sound card D. Monitor 10. The display screen is the most common device used to show you what the computer is doing. A. input B. printing C. output D. electronic 11._________ is a word processing tool that helps you to create quality documents. A. Word 2003 B. Outlook 2003 C. Access 2003 D. Excel 2003 12.The first generation of computer lasted from _________ to 1958. A.1965 B.1946 C.1947 D.1970 13._________ is the application of the computer and communications technology to improve the productivity of office workers. A.CAI B.AI C.OA D.CAM 14._________ is a software system based on graphics, which can run under MS-DOS. A.Office B.Mouse C.OS D.Microsoft Windows 15.Generally software can be divided into two types: software system and _________ system. A.hardware B.DOS C.application D.Windows 16.The _________ is the part of the computer where programs and data are stored. A.Input Device B.Memory C.CPU D.CU 17. refers to data storage equipment that allows the stored data to be accessed randomly rather than just in sequence. A.Random Access Memory B.Magnetic tapes C.Disks D.ROM 18.Word processing , of course, relies on perhaps the most basic computer _________ : the keyboard. A.output device B.input device C.storage D.CPU 19._________ refers to any machine capable of representing information from a
Unit 5 Section A Software Design （软件设计） Design is defined in [IEEE610.12-90] as both “the process of defining the architecture, components, interfaces, and other characteristics of a system or component ” and “the result of that process.” Viewed as a process, software design is the software engineering life cycle activity in which software requirements are analyzed in order to produce a description of the software ’s internal structure that will serve as the basis for its construction. More precisely, a software design (the result) must describe the software architecture -- that is how software is decomposed and organized into components -- and the interfaces between those components. It must also describe the components at a level of detail that enable their construction. Software design plays an important role in developing software: it allows software engineers to produce various models that form a kind of blueprint of the solution to be implemented. We can analyze and evaluate these models to determine whether or not they will allow us to fulfill the various requirements. We can also examine and evaluate various alternative solutions and trade-offs . Finally, we can use the resulting models to plan the subsequent development activities, in addition to using them as input and the starting point of construction and testing. In a standard listing of software life cycle processed such as IEEE/EIA 12207 Software Life Cycle Processes [IEEE 12207.0-96], software design consists of two activities that fit between software requirements analysis and software construction: Software architectural design (sometimes called top level design): describing software ’s top-level structure and organization and identifying the various components. Software detailed design: describing each component sufficiently to allow for its construction.
UNIT 1 词组翻译 1. artificial intelligence 人工智能 2. paper-tape reader 纸带阅读器 3. optical computer 光计算机 4. neural network 神经网络 5. instruction set 指令集 6. parallel processing 并行处理 7. difference engine 差分机 8. versatile logical element 通用逻辑元件 9. silicon substrate 硅衬底 10. vacuum tube 真空管 11. 数据的存储与处理the storage and handling of data 12. 超大规模集成电路very large-scale integrated circuit 13. 中央处理器central processing unit 14. 个人计算机personal computer 15. 模拟计算机analogue computer 16. 数字计算机digital computer 17. 通用计算机general-purpose computer 18. 处理器芯片processor chip 19. 操作指令operating instructions 20. 输入设备input device
完形填空 We can define a computer as a device that accepts input, processes data, stores data, and produces output. According to the mode of processing, computers are either analog or digital. They can also be classified as mainframes, minicomputers, workstations, or microcomputers. All else (for example, the age of the machine) being equal, this categorization provides some indication of the computer’s speed, size, cost, and abilities. Ever since the advent of computers, there have been constant changes. First-generation computers of historic significance, such as UNIVAC (通用自动计算机), introduced in the early 1950s, were based on vacuum tubes. Second-generation computers, appearing in the early 1960s, were those in which transistors replaced vacuum tubes. In third-generation computers, dating from the 1960s, integrated circuits replaced transistors. In fourth-generation computers such as microcomputers, which first appeared in the mid-1970s, large-scale integration enabled thousands of circuits to be incorporated on one chip. Fifth-generation computers are expected to combine very-large-scale integration with sophisticated approaches to computing, including artificial intelligence and true distributed processing. 翻译P9 计算机将变得更加先进，也将变得更加容易使用。 语音识别的改进将使计算机的操作更加容易。 虚拟现实，即使用所有人类官能与计算机进行交互的技术，也将有助于创建更好的人机接口。人们正在开发其他的奇异计算模型，包括使用生物机体的生物计算、使用具有特定属性的分子的分子计算，以及使用遗传基本单位DNA （脱氧核糖核酸）存储数据和执行运算的计算。 这些都是可能的未来计算平台的例子，而它们迄今还能力有限或完全属于理论范畴。 科学家们研究它们，是因为嵌入硅中的电路的微小型化受到物理限制。
计算机专业英语（第四版）课后习题答案 Unit 1 [Ex 1] 1. F 2. T 3. T 4. F 5. T 6. T 7. T 8. T 9. T 10. F [Ex 2] 1. input, storage, processing, and output 2. power; speed; memory 3. central processing unit 4. internal; primary; memory 5. keyboard; central processing unit; main memory; monitor [Ex 3] A. 1. F 2. D 3. G 4. C 5. B 6. A 7. E 8. H B. 1. user 2. monitor 3. data 4. keyboard 5. data processing 6. information 7. computer 8. memory [Ex 4] 1. input device 2. screen, screen 3. manipulates 4. instructions 5. retrieve 6. code 7. hard copy 8. Function [Ex. 5] 新处理器开始IT技术的新时代 New Processors Open New Era of IT Technologies Last week, Intel introduced to the public in Russia and other CIS countries a family of processors Intel Xeon E5-2600. They are more powerful and reliable and, importantly, are very economical in terms of energy consumption. Their presence opens a new era in the field of IT technologies and means that the cloud technology is getting closer. These processors are primarily designed for servers, data centers (DPC) and supercomputers. The emergence of this class of devices is not accidental. According to the regional director of Intel in Russia and other CIS states Dmitri Konash who spoke at the event, the market of IT-technology is developing so rapidly that, according to forecasts, by 2015 there will be 15 billion devices connected to the Internet, and over 3 billion of active users. 上周，英特尔公司向俄罗斯和其它独联体国家的公众推出了英特尔Xeon E5-2600系列处理器，它们更加强大可靠，尤其是在能量消耗方面更加经济实惠。它们的问世意味着IT技术领域开始了一个新时代，标志着云技术距离我们越来越近。 这些处理器主要是为服务器、数字处理中心和超级计算机设计的。这种处理器的出现并非偶然。根据英特尔公司俄罗斯和其他独联体地区负责人Dmitri Konash就此事发表的看法，IT技术市场的发展速度极快，根据预测，到2015年与英特网连接的设施将有150亿，用户超过30亿。 [Ex 6] 1. T 2. T 3. F 4. F 5. T 6. F 7. T 8. F Unit 2 [Ex 1] 1. T 2. F 3. T 4. F 5. T 6. T 7. T 8. F [Ex 2] 1. sizes, shapes, processing capabilities
《计算机英语（第4版）》参考译文 第一单元：计算机与计算机科学 课文A：计算机概览 一、引言 计算机是一种电子设备，它能接收一套指令或一个程序，然后通过对数字数据进行运算或对其他形式的信息进行处理来执行该程序。 要不是由于计算机的发展，现代的高科技世界是不可能产生的。不同类型和大小的计算机在整个社会被用于存储和处理各种数据，从保密政府文件、银行交易到私人家庭账目。计算机通过自动化技术开辟了制造业的新纪元，而且它们也增强了现代通信系统的性能。在几乎每一个研究和应用技术领域，从构建宇宙模型到产生明天的气象报告，计算机都是必要的工具，并且它们的应用本身就开辟了人们推测的新领域。数据库服务和计算机网络使各种各样的信息源可供使用。同样的先进技术也使侵犯个人隐私和商业秘密成为可能。计算机犯罪已经成为作为现代技术代价组成部分的许多风险之一。 二、历史 第一台加法机是法国科学家、数学家和哲学家布莱斯?帕斯卡于1642年设计的，它是数字计算机的先驱。这个装置使用了一系列带有10个齿的轮子，每个齿代表从0到9的一个数字。轮子互相连接，从而通过按照正确的齿数向前转动轮子，就可以将数字彼此相加。17世纪70年代，德国哲学家和数学家戈特弗里德?威廉?莱布尼兹对这台机器进行了改良，设计了一台也能做乘法的机器。 法国发明家约瑟夫―玛丽?雅卡尔，在设计自动织机时，使用了穿孔的薄木板来控制复杂图案的编织。在19世纪80年代期间，美国统计学家赫尔曼?何勒里斯，想出了使用类似雅卡尔的木板那样的穿孔卡片来处理数据的主意。通过使用一种将穿孔卡片从电触点上移过的系统，他得以为1890年的美国人口普查汇编统计信息。 1、分析机 也是在19世纪，英国数学家和发明家查尔斯?巴比奇，提出了现代数字计算机的原理。他构想出旨在处理复杂数学题的若干机器，如差分机。许多历史学家认为，巴比奇及其合伙
计算机专业英语练习参考答案 Unit 1 [Ex 1] 1..F 2.T 3.T 4.F 5.T 6.T 7.T 8.T 9.T 10.F [Ex 2] 1.input, storage, processing, and output 2. power, speed, memory 3. central processing unit 4. internal, primary, memory 5. keyboard, central processing unit, main memory, monitor [Ex 3] A. 1.F 2.D 3.G 4.C 5.B 6.E 7.H 8.A B. https://www.doczj.com/doc/6311713.html,er 2.monitor 3.data 4.keyboard 5.data processing 6. information https://www.doczj.com/doc/6311713.html,puter 8.memory [Ex 4] 1.input device 2. screen, screen 3.manipulates 4.instructions 5.retrieve
6.code 7.hard copy 8.function/code/instruction [Ex 5] 1.T 2.T 3.F 4.F 5.T 6.F 7.T 8.F Unit 2 [Ex 1] 1.T 2.F 3.T 4.F 5.T 6.T 7.T 8.F [Ex 2] 1. sizes, shapes, processing capabilities 2. supercomputer, mainframe computer, minicomputers, microcomputers 3. mainframe computer 4.microcomputers, storage locations 5. portables, laptop computers/ notebook/palm-sized computer, desktop workstations 6.semiconductor 7. CPU, memory, storage, devices, processing, users 8. microprocessor ship [Ex 3] A. 1.C 2.A 3.H 4.I 5.E 6.F 7.G 8.B
2014年下学期《计算机专业英语》期中考试试卷 班级：_________ 姓名：________ 学号：________ 计分：________ I. 根据图片把方框里的单词或词组填入对应的空格。(14分) 1. __________________ 2. _________________ 3. __________________ 4. _________________ 5. __________________ 6. _________________ 7. __________________ II. 中英文配对：将中文前的字母填入其对应的英文前的空格里。（20分） _____ 1. input device a. 闪盘 _____ 2. RAM b. 只读光盘 _____ 3. floppy disk c. 芯片 _____ 4. memory bank d. 移动硬盘 _____ 5. output device e. 输入设备 _____ 6. flash disk f. 随机存储器 _____ 7. chip g. 软盘 _____ 8. mobile hard disk h. 输出设备 _____ 9. motherboard i. 内存条 _____ 10. CD-ROM j. 主板 III. 阅读理解： A Mary: Hello, PC Support Center. This is Mary. What can I do for you? Customer: Hello. this is Chen Lin. I’m calling because I have some questions about my disk. Mary: Hi, Chen Lin. You can tell me one by one. Customer: I’m afraid I’ll run out of disk space. What shall I do? Mary: OK, running out of hard disk space is no big deal. You can just start moving old junks off to the CDs or you can just add a second hard disk. monitor mouse speaker printer system unit
第4单元操作系统 第一部分听力和对话 对话：关于操作系统的讨论 （Henry想要了解更多有关于操作系统的内容，所以他在课后向Mark和Sophie请教） Henry: 一个操作系统可以实现的确切的功能是什么？ Sophie: 它控制包括视觉体验、键盘、鼠标、麦克风以及触摸屏等搜集用户需求的用户接口的关键因素。 Mark：并且在幕后，操作系统忙碌地监控发生在设备内的操作。 Henry: 我了解诸如Wind ows、iOS等很基础的操作系统，但是我认为还有其他的操作系统有很广泛的用途。 Sophie：你说的很对。操作系统可以根据它们在什么设备上使用来进行分类。 Mark：台式机操作系统是为台式机或者手提电脑而设计。你在学校、在家或在工作中使用的电脑大部分都配置有台式机操作系统，如Microsoft Wind ows，OS X，或者Chrome OS。Sophie：另外，像iOS和Android这样的操作系统被定义为移动操作系统，因为它们被设计用于手机、平板电脑、电子书阅读器。 Henry：还有其他的吗？ Sophie：当然。被部署用于网络、文件、应用、数据库、邮件服务器的电脑通常使用可以被多个用户同时使用的分布式网络的服务器操作系统。 Mark：Linux,、UNIX,、Wind ows和OS X服务器都是流行的服务器操作系统。 Henry：太棒了。操作系统究竟存在于哪里？ Mark：在一些诸如手机、电子阅读器的电子设备中，整个操作系统足够小所以可以被储存在只读存储器中。对于其他大多数的电脑，操作系统很大，所以大部分存储在硬盘上或者固态硬盘上。 Sophie：是的。在引导程序的过程中，操作系统内核被加载至随机存取存储器中。内核提供关键的操作系统服务，如内存管理、获取文件。在电脑运行的过程中，内核一直存在于随机存取存储器中。其他的部分如定制化工具，被需要的时候会加载至随机存取存储器中。Henry：我明白了！十分感谢你们。 练习 以小组的形式，用右边的其他表达式来替换文中相应的陈述，组成类似的对话。 听力理解：安卓 安卓是由谷歌和超过30家科技手机公司所组成的开放手机联盟所开发基于Linux的操作系统，是全球范围内使用最广的手机系统。安卓被作为手机设备的基础平台，使得开发者们能够充分利用手机设备能够提供的特性来开发移动应用。因为这是一个开发平台，所以仍和人都能够下载和使用安卓。金冠硬件生产商必须依附某些说明从而能够被称为“安卓兼
中译英参考答案 Unit 1 A computer system consists of hardware system and software system. The hardware of the computer is usually divided into three major parts or three primary subsystems: the CPU, the memory subsystem, and the I/O subsystem. The CPU performs many operations and controls computer. The memory subsystem is used to store program being executed by the CPU, along with the program’s data. The I/O subsystem allows the CPU to interact with input and output devices such as the keyboard and monitor of a personal computer. The components of the computer are connected to the buses. The part of the computer that performs the bulk of data processing operations is called the central processing unit and is referred to as the CPU. In microcomputer, it is often called the microprocessor. The CPU is made up of three major parts: control unit, ALU, and register set. Memory is also known as internal memory or main memory. It refers to the circuits in the computer that hold whatever programs and data are available for immediate use by the CPU. I/O subsystem includes I/O devices and interface. There are a wide variety of I/O devices, such as mouse, printer, sensor, disk, and so on. Input-output interface provides a method for transferring information between internal storage and external I/O devices. Peripherals connected to a computer need special communication links for interfacing them with the CPU. The purpose of the communication link is to resolve the differences that exist between the central computer and each peripheral. Unit 2 Storage hardware provides permanent storage of information and programs for retrieval by the computer. Hard disk drives store information in magnetic particles embedded in a disk. Usually a permanent part of the computer, hard disk drives can store large amounts of information and retrieve that information very quickly. Although fixed hard drive systems offer faster access and have a higher storage capacity than optical discs, optical disc systems use removable media – a distinct benefit. Optical discs – primary CDs and DVDs – are much more widely used than removable hard drive systems. They are the standard today for software delivery, as well as commonly used for storing high-capacity music and video files. There are also versions of both CD and DVD drives available for home audio and home theater use. Optical discs are commonly referred to as compact discs. CD and DVD discs are read by CD and DVD drives. The speed of a CD or DVD drive is rated as 24x, 32x, 36x, and so on. These labels describe how fast the drive is compared to the first version of that drive. For example, a 36x drive is 36 times the speed of the baseline unit that was originally manufactured. Most optical