第一章Computer system overview(操作系统概述)I. Pre-reading Questions1.What is a digital computer?The digital computer is a digital system that performs various computational tasks. The word “digital”implies that theinformation in the computer is represented by variables that take a limited number of discrete values. These values are processed internally by components that can maintain a limited number of discrete states. Digital computer is also called electronic computer or computer.2.Are there any differences between the binary number system and the common decimal number system?The decimal digits has ten digits: 0,1,2,,, and 9. The binary number system has two digits: 0 and 1. The binary numbers use a base 2. The decimal digits use a base 10.3.How many types of computers do you know? Name at least four of them. Computers are usually classified into four broad categories: microcomputers, minicomputers, mainframe computers and supercomputers.II Fill in the following blanks.1.Application software is designed to accomplish real-world tasks in fields.2. An 8-bit signed integer can have any value between -128 and 1273. System software controls the computer and enables it to run the hardware and applications software.4. A computer system consists of hardware system and software system .5. List four types of computers: microcomputers, minicomputers , mainframe computers,and s upercomputers .III True or False.1. The software system is the physical equipment that you can see and touch. 1.F2. Typically, a data value is set to zero to represent FALSE and 1 value forTRUE. 2.F3. In the earliest general-purpose computer, most input and output media were magnetic disks. 3. F4.T4. Supercomputers are largest, fastest, and most expensive computer available.5. A computer system consists of hardware system and software system. 5. T IV Matching terms.1、(b) CPUThe processing unit is at the heart of a computer.2、(c) bit A unit of information conveyed by a single binary digit.3、(a) integrated circuit (IC)A complete electronic circuit that packages transistors and other electronic components on a small silicon chip.4、(d) ASCII A system for encoding characters as binary digits.V Translating Terms.(1) coding techniques 编码技术(2) application software 应用软件(3) floating point data 浮点数据(4) timesharing 分时，分时技术(5) storage capacities 存储容量VI Choose the best one of the four answers given to fill in each blank.This chapter introduces digital computer, data types, the evolution of computers, and types of computers. 1 is known to all, it’s hard to find a field in 2 computers are not being used. Digital computer, also called electronic computer or computer, is a digital system that 3 various computational tasks. Digital computers use the 4 number system, which has two digits: 0 and 1.By usingvarious coding 5 , groups of bits can be made to represent not only binary numbers 6 other discrete symbols, such as decimal digits or letters of the alphabet. A computer system consists of hardware system and software system. Programs tell the hardware what to do. 7 software is designed to accomplishreal-world tasks in fields such as accounting, entertainment, and engineering. Computers are usually 8 into four broad categories: microcomputers, minicomputers, mainframe computers, and supercomputers. It’s hard to give a 9 definition to each type because computer speeds and storage 10 change rapidly.1. A. As B. It C. As it D. That2. A. what B. which C. where D. when3. A. performs B. carries C. makes D. integrates4. A. decimal B. binary C. Arabian D. American5. A. technique B. Technology C. techniques D. technologies6. A. instead of B. rather than C. but also D. as well7. A. Application B. System C. Word D. Excel8. A. put B. made C. conducted D. classified9. A. precious B. progress C. proceeding D. precise10. A. capacities B. capable C. capabilities D. capacity1.A2. B3. A4. B5. C6. C7. A8. D9. D 1 0.CVII. Translate the following into English.1.By using various coding techniques, groups of bits can be made to represent not only binary numbers but also other discrete symbols.通过应用各种编码技术。

一组二进制不但可以表示二进制数据，而且还可以表示其他离散符号，如十进制数字或字母表中的字母。

2.System software includes not only the complex programs used by technicians to create application software in the first place but also the organizational programs另一方面，系needed to start up the computer and govern its use of other programs.统软件控制计算机系统，它不仅包括专业人员用于创建应用软件的复杂程序，而且还包括用于启动计算机和提供给其它程序使用的管理程序。