Chapter5 Computer section 5-4 Software Basics 电气工程及其自动化专业英语课件
电气工程及其自动化专业英语第五单元课件
New Words
central processing unit 中央处理单元
workstation
n. 工作站
mainframe
n. 主机，主机架
supercomputer
超级计算机
server 服务器
client 客户
microcomputer 微型计算机
desktop computer 台式计算机
译为：两台及以上的计算机和其它设备以共享数据和程序为目的连接在 一起可组成计算机网络。
Notes
[12]. One impressive simulation designed to run on a super computer tracked the movement of thousands of dust particles as they were tossed about by a tornado.
operating system 操作系统
Notes
[1]. Most people can formulate a mental picture of a computer, but computers do so many things and come in such a variety of shapes and sizes that it might seem difficult to distill their common characteristics into an all purpose definition.
formulate 是描绘的意思，come in 以…… 形式出现，distill 提取
译为：大多数人都能描绘一台计算机，但由于计算机能做许多事情，有 许多形状和规格，以至于人们难以提取其共同特征形成通用定义。
计算机专业英语教案第5章
第5章Computer Applications5.1 Word Processing5.2 Multimedia5.3 Computer Graphics5.4 Database Applications5.5 Computer Virus5.1 Word Processing•Personal computer-based office automation software has become an indispensable part of electronic management in many countries.•Word processing programs have replaced typewriters; spreadsheet programs have replaced ledger books; database programs have replaced paper-based electoral rolls, inventories and staff lists;personal organizer programs have replaced paper diaries; and so on.•Word processing refers to the methods and procedures involved in using a computer to create, edit, and print documents.•Word processing software has replaced typewriters for producing documents such as reports, letters, papers, and manuscripts.The advantage of word processing•The great advantage of word processing over using a typewriter is that you can make changes without retyping the entire document.•If you want to delete a paragraph, you simply remove it, without leaving a trace.•It is equally easy to insert a word, sentence, or paragraph in the middle of a document.•Word processors also make it easy to move sections of text from one place to another within a document, or between documents.•Most standard word processing features are supported, including footnotes and mail-merge but no tables or columns.•The interface uses customizable toolbars, and the editing screen isa zoom-able draft mode that optionally displays headers, footnotes,and footers.Microsoft Word•Microsoft Word is a powerful word processing application that will allow you, through simple keystroke and menu navigation, to create dynamic documents for work, school, or personal use.•Word processors vary considerably, but all word processors support some basic features.Full-featured word processors usually support the following features •Insert and Delete text•Cut, paste and copy•Page size and margins•Search and replace•Word wrap•Print•File management•Font specifications•Footnotes and cross-references•Graphics•Headers, footers and page numbering•Layout•Macros•Merge•Spell checker•Tables of contents and indexes•Thesaurus•Windows•WYSIWYG(What Y ou See Is What Y ou Get)5.4 Database Applications•Database systems are designed to manage large bodies of information.•The management of data involves both the definition of structures for the storage of information and the provision of mechanisms forthe manipulation of information.• A database-management system (DBMS) consists of a collection of interrelated data and a set of programs to access those data.•The primary goal of a DBMS is to provide an environment that is both convenient and efficient to use in retrieving and storing database information.Transaction Management• A transaction is a collection of operations that performs a single logical function in a database application. Each transaction is a unit of both atomicity and consistency.•Thus, we require that transactions do not violate any database-consistency constraints.•In the absence of failures, all transactions complete successfully, and atomicity is achieved easily.Storage Management•Database typically require a large amount of storage space.•Corporate databases are usually measured in terms of gigabytes or, for the largest databases, terabytes of data.•The performance of a system depends on what the efficiency is of the data structures used to represent the data in the database, and on how efficiently the system is able to operate on these data structures.Database Administrator•The person who has such central control over the system is called the database administrator (DBA).•The DBA creates the original database schema by writing a set of definitions that is translated by the DDL compiler to a set of tables that is stored permanently in the data dictionary.•The DBA also creates appropriate storage structures and access methods by writing a set of definitions, which is translated by the data-storage and data-definition-language compiler.Today's Database Landscape•In addition to the development of the relational database model, two technologies led to the rapid growth of what are now called client/server database systems.•Because processing is split between client computers and a database server, this new breed of application was a radical change from mainframe-based application programming.•The second important technology was the local area network (LAN) and its integration into offices across the world.Distributed Database System•In a distributed database system, the database is stored on several computers.•The computers in a distributed system communicate with oneanother through various communication media, such as high-speed networks or telephone lines.•The computers in a distributed system are referred to by a number of different names, such as sites or nodes, depending on the context in which they are mentioned.5.5 Computer Virus• A computer virus is a program designed to replicate and spread on its own, generally with the victim being oblivious to its existence.•Computer viruses spread by attaching themselves to other programs (e.g., word processor or spreadsheet application files) or to the boot sector of a disk.•Because a virus is software code, it can transmitted along with any legitimate software that enters your environment.•Nearly three-quarters (75 percent) of infections occurred in a networked environment, making rapid spread a serious risk. What’s the Features of Computer Virus?•Computer virus as a procedure can duplicate itself to other normal procedures or on some components of the system, for example, leading portion of disk.•The virus hidden in the infected system does not break out immediately; instead, it needs certain time or some conditionsbefore it breaks out.•Virus will begin attack once some conditions are ready.•Destruction caused by computer virus is extensive, it not only damages computer system, deletes files, or alters data, etc., it can also occupies system resources, disturb machine operation, etc.•Typically, virus can infect several thousand computers in several hours if the infected microcomputer is linked with Internet.•On one hand, new virus or their variations emerge with each passing day; on the other hand, some virus may resurrect after they have been eliminated, for example, when the infected floppy disk are reused.•Virus can transmit normal information as a carrier and thus avoid our protective measures set in the system.•Virus infects through various ways beyond our control, in addition, as illegal duplication and pirate software get popular, detection of virus becomes very difficult.•Virus tends to hide itself to avoid being detected.What’s the Structure of Computer Virus?•Infected sign is also called virus signature composed of ASCII code of some numbers or characters.•Infecting module performs three tasks: To search for an executable file or covered file, to check if there is infected sign on that file,and to infect it, write virus code into the host procedure, if no infected sign is found.•The virus designer attempts in the destructive code to delete files, delete data, format floppy disk and hard disk, decrease computer efficiency and space, etc.•If the condition is ready, the triggering module returns “true” value, and calls destroying module to destroy, otherwise it returns a “false” value.•Major control module controls the four modules mentioned above.Besides, it also ensures the infected program can continue to work normally and no deadlock will occur in contingency.What damage Can Viruses Do?•Some viruses are merely annoying, and others are disastrous.•At the very least, viruses expand file size and slow real-time interaction, hindering performance of your machine.•Other viruses are more dangerous.•They can continually modify or destroy data, intercept input/output devices, overwrite files and reformat hard disks.What Are the Symptoms of Virus Infection?•Changes in the length of programs•Changes in the file date or time stamp•Longer program load time•Slower system operation•Reduced memory or disk space•Bad sectors on your floppy•Unusual error messages•Unusual screen activity•Failed program execution•Failed system boot-ups when booting or accidentally booting from the A drive•Unexpected writes to a driveWhat Are the Effects of Computer Virus to the Society?•Some viruses create disgust effects or frighten the user, such as interfering the keyboard or displaying disgusting messages or pictures.•Computer viruses can be a great threat to a company. A company may lose important documents which may mean the lost of capital.•One step further, the operation breakdown of companies causes prelims to the society’s normal operation.。
Chapter 5ComputerOrganization
Control Unit
• Controlling is achieved through wires that can be on or off.
5.2 MAIN MEMORY
Figure 5-3
Main memory
Address space
Table 5.1 Memory units
Unit ----------kilobyte megabyte gigabyte terabyte petabyte exabyte
Example 2
A computer has 128 MB of memory. Each word in this computer is 8 bytes. How many bits are needed to address any single word in memory?
Solution
Continued on the next slide
OBJECTIVES (continued)
Understand the systems used to connect different components together.
Understand the addressing system for input/output devices. Understand the program execution and machine cycles.
The memory address space is 128 MB
（ 227）. However, each word is 8 (23) bytes,
which means that you have 224 words. This means you need log2 224 or 24 bits, to address each word.
《计算机英语》课后习题答案
《计算机英语》参考答案Chapter 11.(1) 中央处理器(Central Processing Unit)(2) 随机访问内存(Random-access Memory)(3) 美国国际商用机器公司(International Business Machine)(4) 集成电路(Integrated Circuit)(5) 大规模集成电路(Large Scale Integration)(6) 超大规模集成电路(Very Large Scale Integration)(7) 个人数字助理(Personal Digital Assistant)(8) 图形用户界面(Graphical User Interface)2.(1) data(2) software(3) IC(4) ENIAC(5) supercomputer(6) superconductivity3.(1) F (ENIAC is the second digital computer after Atanasoff-Berry Computer)(2) T(3) F (Data is a unorganized)(4) T(5) T(6) T4.(1) 人工智能(2) 光计算机(3) 神经网络(4) 操作系统(5) 并行处理(6) vacuum tube(7) integrated circuit(8) electrical resistance(9) silicon chip(10) minicomputer5.数据是未经组织的内容的集合，数据可以包括字符、数字、图形和声音。
计算机管理数据，并将数据处理生成信息。
向计算机输入的数据称为输入，处理的结果称为输出。
计算机能在某一个称为存储器的地方保存数据和信息以备后用。
输入、处理、输出和存储的整个周期称为信息处理周期。
与计算机交互或使用计算机所产生信息的人称为用户。
1.(1) 发光二极管(Light-Emitting Diode)(2) 静态随机存储器(Static Random Access Memory)(3) 只读存储器(Read Only Memory)(4) 运算器(Arithmetic and Logical Unit)(5) 阴极射线管(Cathode Ray Tube)(6) 视频显示单元(Visual Display Unit)(7) 可编程只读存储器(Programmable Read Only Memory)(8) 液晶显示屏(Liquid Crystal Display)2.(1) CPU(2) peripheral(3) memory(4) modem(5) control unit(6) byte3.(1) T(2) T(3) F (RAM is volatile memory because the information within the computer chips is erased as soon as the computer is powered off whereas ROM is nonvolatile)(4) T(5) T(6) F (Microphones and digital cameras are input devices)4.(1) 寄存器组(2) 主机(3) 二进制的(4) 算法(5) 光盘(6) CD-RW(7) logic operation(8) barcode(9) peripheral device(10) volatile memory5.计算机的内存可被视为一系列的单元，可以在单元中存取数字。
Unit_4-Software_Development
• 计算机程序是指挥计算机执行某种处理功能或 功能组合的一套指令。
For the instructions to be carried out, a computer must execute a program, that is, the computer reads the program, and then follows the steps encoded in the program in a precise order until completion.
• 操作系统管理计算机以及与之相连的各种资源和设 备，如随机存储器、硬盘驱动器、监视器、键盘、 打印机和调制解调器，以便其他程序可以使用它们。 操作系统的例子包括：DOS、Windows 95、OS/2 和UNIX。
• Software designers create new programs by using special applications programs, often called utility programs or development programs. • 软件设计者使用经常被称为实用程序或开发程序的 专门应用程序来创建新程序。
一个程序可多次执行，而且，取决于用户提供 给计算机的选项和数据，每次执行可能产生不 同的结果。
Programs fall into two major classes: application programs and operating systems. An application program is one that carries out some function directly for a user, such as word processing or game playing. 程序分为两大类：应用程序和操作系统。应用程 序直接为用户执行某种功能，如处理文字或玩游 戏。
计算机专业英语第三版教学课件Unit5 Software Engineering
布朗先生：您好！中华计算机公司。我能为您做些什么？
Linda: Hello, Mr. Brown. It is Linda. Got a minute?
琳达：您好，布朗先生。我是琳达。您有时间吗？
Mr. Brown: I see your point. If we have to spend more time on developing the second version, we’ll have to adjust the schedule. People need to know that we have adjusted the project development plan as soon as possible. Do you want me to call the project manager?
Look and Learn Dialogue Reading Learn More New Words and Phrases
A software development project organization.
Lesson 14
Unit 5
Look and Learn Dialogue Reading Learn More New Words and Phrases
Mr. Brown: Yes.We planned to put the two versions in the same development process. Well, what kind of problem are you having now?
布朗先生：是的。我们计划在同一个开发过程中投入两个版本。那您现在遇到什么问题了？
人教版高中英语选修计算机英语ChapterSummary(5)
Application software
Thare:
Make business activities more efficient
Assist with graphics and multimedia projects
Support home personal and educational tasks
Application software
What is system software?
• Serves as the interface between the user, the application software and the computer’s hardware.
• To use application software, you must have system software as the platform.
Allow users create, access, and manage the data.
You can add, change, delete, sort and retrieve the data.
Common application softwares What is presentation graphics
Application software
How do you start an application?
• From the desktop, click the start button, point to All Programs and click the name of application.
Facilitate communications
Application software
《计算机英语》Unit 5
1.1 Object-Oriented Programming
• III. Translating.
– 1. Original: Object-oriented programming was deployed in part as an attempt to address this problem by strongly emphasizing discrete units of programming logic and re-usability in software – Translation: – 2. Original In the past decade Java has emerged in wide use partially because of its similarity to C and to C++, but perhaps more importantly because of its implementation using a virtual machine that is intended to run code unchanged on many different platforms. – Translation:•来自Complex Sentences
1.2 Introduction to the C# Language and the .NET Framework
– 2. Original: In addition to the run time services, the .NET Framework also includes an extensive library of over 4 000 classes organized into namespaces that provide a wide variety of useful functionality for everything from file input and output to string manipulation to XML parsing, to Windows Forms controls. – Translation:除了运行时服务，.NET Framework 还包括一个巨大 的类库，有超过4 000 个被组织到命名空间中的类。这个类库提 供了多种有用的功能，从文件输入输出到串操作，到XML解析， 再到Windows 表格控件。
《计算机专业英语》Unit 5 What is Operating System
The patterns are very diverse operating systems; OS can be installed on different machines from simple to complex, from the phone's embedded systems to large-scale supercomputer operating system. Many operating systems, the definition of manufacturer of the OS is not much consensus, for example, that some OS integrated graphical user interface, and some OS to use only a text interface, while the graphical interface as a non-essential applications.
资源, 财力, 办法, 智谋
经营, 管理, 处理, 操纵, 驾驶, 手段
Novell公司出的网络操作系统
植入的, 深入的, 内含的
Computer Software-阅读理解
take the form of 采取...形式 entity n.实体; 统一体
modular design 标准设计, 模块化设计 object-oriented 面向对象的
stub n.树桩, 桩模块
trial-and-error n.试错，反复试验
give way to 让路,让步 malfunction n.故障，出错 analogy n.类似, 类推 stark adv.完全地 non-structure 非结构性 contradiction n.反驳, 矛盾
计算机专业英语
6-11
Chapter 6
Software Engineering
6.1.1 The Cycle as a Whole Regardless of why software enters the modification phase, the process requires that a person (often not the original author) study the underlying program and its documentation until the program, or at least the pertinent part of the program, is understood. Otherwise, any modification could introduce more problems than it solves.
Chapter5 Computer section 5-5 Computer Network Basics 电气工程及其自动化专业英语课件
Section 5 Computer Network Basics
（ 5 ） Computer power can be increased by combining multiple CPUs or computers work together. Grouping multiple CPUs means that multiple processes can be executed simultaneously. As another approach, a program may be executed more rapidly by distributing its execution so that each connected CPU or computer may be executing different parts of the program.
Section 5 Computer Network Basics
covering. Unlike twisted pair and coaxial cables, fiber-optic cables do not conduct or transmit electrical signals. Instead, miniature lasers convert data into pulses of light, which flash through the cables. ቤተ መጻሕፍቲ ባይዱables are an essential part of the Internet backbone, and are increasingly found on business and campus networks.
Section 5 Computer Network Basics
《计算机英语》 司爱侠,人民邮电出版社答案
Text A I. Complete the following sentences according to the information in the text.1. programmable, analog, digital2. continuous, discrete3. billing, shipping, receiving, inventory control4. computations, MPU, CPU5. Complex Instruction Set Computer6. Digital Signal Processing7. integer, logic8. buses, pulses,9. Random Access Memory, internal10. keyboards, mouse, monitors, printersII. Translate the following terms and phrases into Chinese.1. external devices 1. 外部设备2. output device 2. 输出设备3. parallel device 3. 并行设备4. assembly language 4. 汇编语言5. block device 5. 块设备6. floating point 6. 浮点7. data stream 7. 数据流8. input device 8. 输入设备9. integrated circuit 9. 集成电路10. main storage 10. 主存III. Translate the following terms and phrases into English.缩写完整形式中文意义1. ALU Arithmetic/Logic Unit 运算器2. CPU Central Processing Unit或CentralProcessor Unit中央处理器3. CISC Complex Instruction Set Computer 复杂指令集计算机4. DSP Digital Signal Processing 数字信号处理5. EPROM Erasable Programmable Read OnlyMemory 可擦可编程只读存储器6. LED light-emitting diode 发光二级管7. MODEM MOdulator, DEModulator 调制解调器8. RAM Random Access Memory 随机访问存储器9. ROM Read Only Memory 只读存储器10. RISC Reduced Instruction Set Computer 精简指令集计算机IV. Fill in the gaps with the words or phrases chosen from the box. Change the forms where necessary.1. instructions 2. devices 3. concept 4. consuming 5. integrated circuits6. space7. fit into8. Information Age9. embedded computer 10. controlV. Translate the following passage into Chinese.计算机能够储存和执行被叫做程序的许多指令，这使其非常通用并不同于计算器。
计算机专业英语2013影印版unit_5
5 System Software
System software is not a single program. Rather it is a collection or a system of programs that handle hundreds of technical details with little or no user intervention.
设备驱动是特殊的程序可以允许特别的输入或输出设备 能够与计算机系统其他部分进行通信。
Language translators convert the programming instructions written by programmers into a language that computers understand and process.
热启动-电脑已经开启，然后你点击重新启动，不关闭 电源。重启，重启
冷启动-电脑已经关闭，启动电脑被称为冷启动
5.1.2 Features
You typically interact with the operating system through the graphical user interface. Most provide a place, call the desktop, which provides access to computer resources.
操作系统协调计算机资源，提供用户和计算机之间的接口， 并运行应用程序。实用程序执行有关管理计算机资源相关 的具体任务。
5.1 Operating System
Device drives are specialized programs that allow particular input or output devices to communicate with rest of the computer system.
计算机英语学生用书(第二版)习题答案chapter 05.
II. True or False III.Answering Questions IV. Translating Terms
Vocabulary
V. Selecting Words
Collocation Summary
• First generation—— machine language • Second generation—— assembly language • Third generation—— high-level languages • Fourth generation—— very-high-level
5. T
IIV. Exercises—Comprehension
III. Answer the following question.
1. List the five steps of programming.
1. Programming is traditionally a five-step problem-solving process. The five steps are as follows: The first step: Problem definition The second step: Program design The third step: Program coding The fourth step: Program testing The fifth step: Program documentation and maintenance
languages • Fifth generation—— natural languages
Computer English Unit 5 Software Process(计算机英语 第五单元 软件过程)
Unit 5 Software Process第五单元：软件过程Section A Software Process Models课文A：软件过程模型Ⅰ.Introduction一、引言A software process is a set of activities that leads to the production of a software product. These activities may involve the development of software from scratch in a standard programming language like Java or C. Increasingly, however, new software is developed by extending and modifying existing systems and by configuring and integrating off-the-shelf software or system components.一个软件过程是生产出软件产品的一系列活动。
这些活动可能涉及使用一种像Java或C这样的标准编程语言从零开始开发软件。
然而，开发新软件越来越多地使用的方法是，扩展和修改现有系统，以及配置和集成现成软件或系统组件。
A software process model is an abstract representation of a software process. Each process model represents a process from a particular perspective, and thus provides only partial information about that process. This section introduces a number of very general process models (sometimes called process paradigms) and presents them from an architectural perspective. That is，we see the framework of the process but not the details of specific activities.一个软件过程模型是对一个软件过程的一种抽象表示。
(完整word版)计算机专业英语教程(第5版)翻译完整版
主存储器，也就是说内存，用于为处理器暂时存放程序和数据。所有的程序和数据在被操作之前必须从输入设备（如VDT）或者辅助存储器转存到主存储器中。主存储器存储容量通常是相当有限的，因此，在一个程序执行结束，它所占用的存储空间必须被重新分配给其它正在等待执行操作的程序。
Figure 1-1 illustrates how all input/output (I/O)is “read to” or “written from” primary storage. In the figure, an inquiry (input) is made on a VDT. The inquiry, in the form of a message, is routed to primary storage over a channel (such as a coaxial cable). The message is interpreted, and the processor initiates action to retrieve the appropriate program and data from secondary storage [3].The program and data are “loaded”, or moves, to primary storage from secondary storage. This is a nondestructive read process. That is, the program and data that are read reside in both primary storage (temporarily) and secondary storage (permanently). The data are manipulated according to program instructions, and a report is written from primary storage to a printer.
Unit4-Software Development解读
Unit 4 Software Development
7
A programmer uses another type of program called a text editor to write the new program in a special notation called a programming language. text editor文本编辑程序，文本编辑器 notation[nəʊ’teɪʃn] n.记号，符号，标记法 程序员还使用另一种称为文本编辑器的程序来编写新程 序，新程序是用称为程序设计语言的特殊符号来编写的。
Unit 4 Software Development 6
定语从句
Ⅱ. Program Development （程序开发） Software designers create new programs by using special applications, often called utility programs or development programs.
Unit 4 Software Development
2
For the instructions to be carried out, a computer must execute a program, that is, the computer reads a program, and then follows the steps encoded in the program in a precise order until completion. carry out执行；进行；完成 encode[ɪn'kəʊd] vt.（将文字材料）译成密码；编码，编 制成计算机语言 要使程序中的指令得到执行，计算机必须执行该程序， 也就是说，计算机要读取该程序，然后按确切的顺序执 行程序中编码的步骤，直至程序结束。
电气工程专业英语Chapter5
Chapter 5 Computer 第五章计算机Most people can formulate构想出a mental内心的picture of a computer,but computers do so many things and come in such a variety of shapes and sizes that it might seem difficult to distill提取精华their common characteristics into an all-purpose definition通用定义.大多数人都能对计算机有感性认知，但是计算机可以做很多的事情，而且还有各种形状和规格，以至于很难用一个通用定义来概述其常用特征。
At its core,a computer is a device that accepts input, processes data,stores data,and produces output,all according to a series of stored instructions指令.就其实质来说，计算机是一个根据一系列已储存的指令来接收输入数据，处理数据，存储数据和产生输出数据的设备。
Computer input is whatever is put into a computer system.计算机输入指的是任何输入到计算机系统中的东西。
Input can be supplied by a person,by the environment,or by another computer.可以由人、环境或别的计算机来提供输入。
Examples of the kinds of input that a computer can accept include the words and symbols in a document,numbers for a calculation,pictures,temperatures from a thermostat恒温器, audio音频signals from a microphone,and instructions from a computer program.例如：计算机可以接收的输入数据类型有文档中中文字和符号、计算器的数字、图片、恒温器传来的温度、麦克风出啊来的音频信号和计算机程序中指令。
计算机专业英语教程(第5版)翻译完整版
1.1 A Closer Look at the Processor and PrimaryStorage仔细看看处理器和主存储器We have learned that all computers have similar capabilities and perform essentially the same functions, although some might be faster than others. We have also learned that a computer system has input, output, storage, and processing components; that the processor is the “intelligence” of a computer system; and that a single computer system may have several processors. We have discussed how data are represented inside a computer system in electronic states called bits. We are now ready to expose the inner workings of the nucleus of the computer system — the processor.我们已经知道，所有的电脑都具有相似的能力，并且在本质上执行相同的功能，尽管一些可能会比另一些快一点。
我们也知道，一个电脑系统具有输入，输出，存储和处理部件；处理器是一个电脑系统智能核心，并且一个电脑系统可以有许多个处理器。
我们已经讨论过如何在电脑系统内部，用被称作“位”的电子状态来表现数据，现在我们要弄明白电脑系统的核心，即处理器，的内在的工作方式。
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of the instructions in a program as a single batch,
and the resulting machine language instructions,
called object code, are placed in a new file. As an
into machine language is more common with Web-
based programs called scripts, written
in
languages such as JavaScript and
Section 4 Software Basics
VBScript. These scripts contain high-level instructions, which arrive as part of a Web page. An interpreter reads the first instruction in a script, converts it into machine language, and then sends it to the microprocessor. After the instruction is executed, the interpreter converts the next instruction, and so on. Programs written for a computer may be in one of the following categories: （ 1 ） Binary code. This is a sequence of instructions and operands in binary that list the
Chapter 5 Computer
Section 4 Software Basics
A support module provides an auxiliary set of instructions that can be used in conjunction with the main software program. Each module is stored in its own file. Unlike a program file, a support module is not designed to be run by the computer user. Instead, these modules are "called" by the computer program, as needed.
Software is categorized as either system software or application software. System software helps you to manage your files, to load and execute programs, and to accept your commands from the mouse and keyboard. The system software programs that manage the computer are collectively known as an
A data module, as you might expect, contains any data that is necessary for a task, but not supplied by the user. For example, word processing software checks spelling by comparing the words in
Section 4 Software Basics
exact representation of instructions as they appear in computer memory. （ 2 ） Octal or hexadecimal code. This is an equivalent translation of the binary code to octal or hexadecimal representation. （3）Symbolic code. The user employs symbols (letters, numbers, or special characters) for the operation part, the address part, and other part of the instruction code. Each symbolic instruction can be translated into one binary coded instruction. This translation is done by a special program called an
Section 4 Software Basics
operating system, and differ from the application programs, such as Microsoft Word, or Netscape, or the programs that you write, which you normally run to get your work done. Windows and UNIX are the best known examples of an operating system. The operating system is an essential part of the computer system. Like the hardware, it is made up of many components. A simplified representation of an operating system is shown in Fig.5-1. the most obvious element is the user interface that can be defined as the combination of hardware and
alternative to a compiler, an interpreter converts one
instruction is running.
This method of converting high-level instructions
Section 4 Software Basics
high-level language into machine language can be
accomplished by two special types of programs:
compilers and interpreters. A compiler translates all
Section 4 Software Basics
a document with the words in a dictionary file of correctly spelled words.
When a computer programmer develops or writes software, he has to select a suitable computer language that provides the tools that he uses to create software. These languages help the programmer produce a lengthy list of instruction, called source code, that defines the software environment in every detail—how it looks, how the user enters commands, and how it manipulates data. Most programmers today prefer to use high-level
A computer's microprocessor only understands machine language in binary form—the instruct set that is "hard wired" within the microprocessor's circuits. Therefore, instructions written in a highlevel language must be translated into machine language in binary form before a computer can use them. The process of translating instructions from a
Section 4 Software Basics
software that helps people and computers communicate with each other. Your computer user interface includes the mouse and keyboard that accept your input and carry out your commands, as well as the display device that provides cues to help you use software, and displays error messages that alert you to problems. An operating system typically provides user interface tools, such as menus and toolbar buttons, which define the "look and feel" for all of its compatible software. Most computers today feature a graphical user interface.