Chapter 2 Computer Systems
Chapter 2
Computer Systems
Objectives and Overview
Chapter 2 is the first of a trio of chapters devoted to the primary building blocks of information
technology. Chapter 2 concentrates on computer systems, including both the hardware the
physical pieces of a computer system and the software the set of programs that controls the
operations of the computer system. Chapter 3 covers telecommunications and networking, and
Chapter 2 in the Seventh Edition is a brand new chapter, incorporating (in greatly reduced form)
the material that was covered in Chapter 2, Computer Hardware, and Chapter 3, Computer
Software, in the Sixth Edition of this book. The primary objective of Chapter 2 is to provide the
It may be useful to view this chapter as consisting of five major sections two of these are
primarily devoted to computer hardware, two more are primarily devoted to computer software,
and the fifth section is devoted to the information technology (IT) industry. The first major
After a short introduction to the two key types of software applications software and support
software, the third major section on applications software includes an example of an application
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interface software. We suspect this section will be mostly new for students unless they have an
extremely strong computing background. After a short section on the changing nature of
o include new boundaries between the
categories as well as updated lists of the major vendors in each category. The boxes on blade
The specific objectives of this chapter are:
2. To describe the all-important stored-program concept, which is the basis for the way in
which all computers operate today.
3. To describe the different categories of computers, including microcomputers, midrange
5. To introduce the idea of purchased applications packages.
6. To consider the variety of personal productivity software packages such as word
7. To consider the wide variety of functions accomplished by the operating system and to
8. To consider the makeup and changing composition of the different components of the
information technology (IT) industry.
The difficulty in teaching Chapter 2 lies in correctly assessing the computer systems background
of the majority of the class and adjusting classroom time and material accordingly. Most of
packages, and they know a little about the Windows operating system. However, unless they
Our suggestion is to tell the students, in advance, that some of the material may be review for
them, and that they may skim subsections with which they are familiar. Furthermore, tell the
students that they should not be concerned with the mechanical details of the sample programs
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given in the text these samples are provided merely to give students the flavor of the various
Teaching Suggestions
The primary difficulty in teaching this chapter lies in correctly assessing the level of computing
knowledge of a given class and adjusting the classroom sessions accordingly. It is important to
to cater to the few students who have an excellent computing background, or to the few who
know nothing at all about computers.
For most courses using this textbook, we believe that you should allot from two to four 75-minute
classroom sessions to Chapter 2 and related enrichment activities. For courses where most
students have a good computing background, two sessions should suffice. We would suggest
using a –
making sure that students understand the underlying structure of all computer systems, the stored-
program concept, and the roles of the different types of computers in use today. On this latter
topic (the roles of different types of computers), enliven the discussion by bringing in very recent
statistics or news clippings describing recent events in the rapidly changing hardware industry
(Which vendor is leading in server sales? Which smartphone is in the lead in terms of business
employ an enrichment activity related to computer hardware or computer use in general. For
For the second classroom session for a course in which most students have a good computing
background, we suggest concentrating on computer software, the IT industry, and a related
enrichment activity. Again, we suggest using about half of the class peri –
students understand the difference between applications software and support software; the roles
of the operating system and other support software; and the notions of fourth generation
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In a course in which most students do not have a good computing background for example, an
advanced undergraduate course where the students have had only a single computer tools course
(e.g., Microsoft PowerPoint, Microsoft Excel, Microsoft Access) we believe that you might
need four 75-minute sessions to cover Chapter 2 two of these sessions on computer hardware
and two on computer software and the IT industry. For the first session, we suggest a traditional
lecture-discussion approach to cover the computer hardware portion of the chapter, making sure
that students understand the underlying structure of all computer systems, the stored-program
For the second session, devote the entire class session to one or more enrichment activities.
Three options were mentioned above: Case Study 1, Midsouth Chamber of Commerce (A): The
Role of the Operating Manager in Information Systems; Case Study I-1, IMT Custom Machine
Company, Inc.: Selection of an Information Technology Platform; or video presentations about
For the third session, we suggest a traditional lecture-discussion approach to cover the computer
software and IT industry portions of the chapter. Make sure that students understand the
difference between applications software and support software; that they understand the roles of
the operating system and other support software; and that they understand the notions of fourth
generation languages (4 GLs), eXtensible Markup Language, object-oriented programming, and
W
For the fourth session, we again suggest devoting the entire class session to one or more
enrichment activities. Two options mentioned above were Case Study I-6, HH Gregg: Deciding
on a New Information Technology Platform, and the demonstration of a software package that
most of your students will not know, such as the Adobe Systems PageMaker desktop publishing
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Of course, these two options two-session coverage of this chapter and four-session coverage of
this chapter are only two of the many options. If your class, on average, has an excellent
computer background, you may choose not to cover the chapter at all in class, but rather suggest
that your students read the chapter as background reading. Even in this case, we would urge you
Review Questions
1. Distinguish between microcomputers, midrange systems, mainframes, and
supercomputers. Give approximate speeds (millions of floating point operations per second,
or MFLOPS) and costs.
Microcomputers, or PCs, may be desktops, notebooks, or palmtops. They are used for personal
computing, Web clients, clients in client/server applications, and small business processing.
MFLOPS range from 500 to 5,000. They cost from under $200 to $4,000.
Midrange systems are used for departmental computing and for specific applications such as
office automation and computer-aided design. They are servers in client/server applications and
2. List the six building blocks that make up digital computers, and describe the flows of
data that occur among these blocks.
3. What are the advantages and disadvantages of using direct access files versus using
sequential access files? Why do organizations bother to use sequential access files today?
Sequential access files are organized in order according to the control key of each file. Because
there are no addresses in a sequential access file, the only way the computer can find a specific
record is to start at the beginning of the file and read each record until it reaches the desired one.
4. Explain in your own words the importance of the stored-program concept. Include the
role of the control unit in your explanation.
A stored program consists of a set of operating instructions that provides a precise listing of
exactly what the computer is to do, prepared in a form that the control unit of the computer has
been built to understand. Most importantly, the control unit carries out these instructions at
5. What is a blade server and why have blade servers become important in the last few
years?
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A blade server (also referred to as a blade) is a very narrow, compact server that can be placed
into a blade server chassis along with several other blade servers. For example, one variation of a
6. Four categories of computer systems were considered in this chapter: microcomputers,
midrange systems, mainframes, and supercomputers. Provide the name of at least one
prominent vendor in each of these categories (and you can use IBM only once!).
7. Briefly describe the four generations of computer programming languages, concentrating
on the major differences among the generations. How does object-oriented programming
fit into these generations? How does HTML fit into these generations?
The first generation language (1 GL) is machine language that the specific computer model is
built to understand. A machine language instruction consists of an operation code and one or
more addresses. The second generation language (2 GL) is assembly language, in which machine
language codes and addresses are replaced by easily remembered mnemonic codes and symbolic
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8. List at least five categories of personal productivity software packages. Then concentrate
on one of these categories, and describe a representative product in that category with
which you are somewhat familiar. Provide both strong points and weak points of the
particular product.
Personal productivity software includes presentation graphics, word processing, spreadsheet,
database management, electronic mail, and calendaring and scheduling programs.
A presentation graphics product is Microsoft PowerPoint. It is easy to use and provides
customized options. Its clip art and background options are somewhat limited, but getting better.
A word processing product is Microsoft Word. It underlines misspelled words and grammatical
errors, it allows for easy formatting changes, and it allows importing of spreadsheets and
9. List the six major categories of support software.
10. What are the primary advantages of a fourth generation language over a third
generation language? What are the primary disadvantages?
A 4 GL program requires fewer instructions than an equivalent 3 GL program, and once the
user knows the 4 GL language a 4 GL program is easier to write, easier to modify, easier to read
Chapter 2 Computer Systems
11. What are the primary characteristics of an object-oriented language? How does an
object-oriented language differ from a third generation language or a fourth generation
language?
12. For what does the CASE acronym stand? In general, what is the purpose of CASE
tools? What types of individuals are most likely to use CASE tools?
13. List at least three independent software houses (not associated with a computer vendor)
that are major players in the software component of the information systems industry. List
any software products that you regularly use and indicate the firm that developed each
product.
Microsoft, Oracle, SAP, Computer Associates, and Adobe Systems are major independent
14. Provide the full names for the following acronyms or abbreviations used in this chapter.
OCR: optical character recognition, an input method that directly scans typed, printed,
or hand-printed material
CPU: central processing unit, which includes the control unit and the arithmetic/logical
unit
Chapter 2 Computer Systems
DVD: digital video disk or digital versatile disk, a newer type of CD that holds several
gigabytes of data; some of these are rewritable
DBMS: database management system, a type of support software that is used to store,
modify, and manage data and to make that data accessible in a variety of
meaningful and authorized ways
Discussion Questions
1. Some commentators have suggested that mainframe computer systems could be squeezed
out of existence in the next few years, with the incredible advances in the capabilities of
midrange systems and the power of supercomputers combining to divide up the present
mainframe market. What do you think? Why?
2. What are the advantages and limitations of palmtop or handheld computers (including
smartphones)? Do you have one? If so, for what do you use it? If not, what features would
be particularly attractive to you?
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3. What are the advantages and limitations of a tablet PC? Do you believe tablet PCs will
be successful? Why or why not? Do you see yourself using a tablet PC in a few years?
The answer to this question became more complex when the Apple iPad was introduced in April
2010. Until that time, the major advantage for tablet PCs was that handwritten notes could be
tal form such that they could be recalled and
modified as desired. Otherwise, these full-function tablet PCs acted like any other PC. For these
tablet PCs, the limitations were that the tablet PC was somewhat heavier and more awkward to
4. With one firm (IBM) dominating the mainframe hardware market in the United States
since its inception, and with that same firm currently near the top in every segment of the
hardware industry (except microcomputers), has the computer hardware industry truly
been competitive over the past five decades? Support your position.
5. List possible uses of a supercomputer in a business setting.
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6. For most business information processing, what do you believe are the critical or limiting
CPU speed, memory capacity, DASD
capacity, internal communication speed, input-output speed, other factors, or some
combination of these factors? Justify your answer.
7. Which one category of personal productivity software is of most value to you now as a
student? Why? Within this category, what is your favorite software package? Why? Do
you think that the one category of personal productivity software of most value to you will
change as you move into your career? Why?
One possible answer to the first part of the question: Word processing is most important now
because I continually write reports, outlines, and class notes. I use Microsoft Word because there
8.
and T-shirts bearing the word COBOL within the international symbol for not permitted (a
red circle with a red line diagonally across the word COBOL). Do you think the movement
will ever be successful? Why?
COBOL has proved its usefulness as a procedural language and is still important. COBOL is
widely used and relatively easy to learn; the majority of business applications on mainframe
computers still employ COBOL programming. COBOL offers the advantage of machine
9. You have probably had experience with at least one procedural (3 GL) language in either
high school or college. What are the strengths and weaknesses of the particular language
that you know best? Based on what you have gleaned from the text, what primary
advantages would a nonprocedural 4 GL offer over the 3 GL that you know best? What
disadvantages?
10.
competing frameworks for developing Web applications. Explore J2EE and .NET in more
detail by discussing the two frameworks with programmers you know and by conducting
research using the Web. Are there other differences between the two frameworks? How
11. As you have read in newspapers and magazines, one firm seems to dominate the
worldwide software market Microsoft. With this degree of dominance by one firm, has
the software industry truly been competitive, particularly over the past decade? Support
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your position.
As evidenced by relatively high software prices, competition has been less than optimal over the
last decade. Development costs are high for competitive applications, and unit sales must be high
12. In the late 1990s, the U.S. government, joined by several state governments, brought suit
against Microsoft, arguing that Microsoft unfairly exercised monopoly power in the
software industry. What was the outcome of these lawsuits? The European Union also
brought suit against Microsoft for exercising monopoly power. What was the outcome of
the European Union lawsuit? (Use the Web to conduct your research.)
For the federal antitrust case, the trial judge found for the government and against Microsoft, and
ordered Microsoft to be split into two companies, an operating system company and an
applications software company. On appeal, the court of appeals agreed that Microsoft had
exercised
appeals required Microsoft to change some of its marketing practices to be less predatory. For
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