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Extended Learning Module A
Computer Hardware and Software
Define information technology (IT) and its two basic categories: hardware and software.
Describe the categories of computers based on size.
Compare the roles of personal productivity, vertical market, and horizontal
market software.
Describe the roles of operating system and utility software as components
of system software.
Define the purpose of each of the six major categories of hardware.
A Quick Tour of Technology
Information technology (IT) is any computer-based tool that people use to work
with information and support the information and information-processing needs of an
organization. IT includes the Internet, spreadsheet software, a satellite, a gamepad for
playing video games … the list of the technology you can find in your immediate life is
almost endless (see Figure A.1). There are two basic categories of information technology:
hardware and software. Hardware consists of the physical devices that make up a computer, for instance, keyboard, mouse, modem, flash memory drive (also called a thumb
drive), and printer. Software is the set of instructions your hardware executes to carry
out a specific task for you such as creating a graph (spreadsheet software, for example)
and surfing the Web (Internet Explorer, for example). Hardware and software in aggregate
are what people refer to as a computer, and even that term is becoming more blurred each
day with digital media players, cell phones, and the like.
Computer Hardware and Software
PC video camera
Figure A.1
Information Technology
(IT) Includes Many Tools
Smart watch
Tablet PC
Haptic gaming
Digital camera picture printer
Extended Learning Module A
All hardware falls into one or another of six categories. Here’s a quick summary.
1. Input: Input devices are tools you use to enter information and commands.
2. Output: Output devices are tools you use to see, hear, or otherwise recognize the
results of your information-processing requests.
3. Storage: Storage devices are tools you use to store information for use at a later time.
4. Processing: The central processing unit (CPU) is the actual hardware that
interprets and executes the software instructions and coordinates the operation
of all other hardware. RAM, or random access memory, is a temporary
holding area for the information you’re working with, as well as the system and
application software instructions that the CPU currently needs.
5. Telecommunications: A telecommunications device is a tool you use to exchange
information with another person or computer in a network. Telecommunications,
as a field, and its associated devices, is so broad that we’ve devoted an entire
module to the topic. Please read Extended Learning Module B (Network Basics) to
learn about cable and DSL modems, home networks, fibre optics, and much more.
6. Connecting: Connecting devices include such things as USB ports into which you
connect a printer and connector cords.
The two main types of software are application and system software. Application
software is the software that enables you to solve specific problems or perform specific
tasks. Microsoft PowerPoint, for example, can help you create slides for a presentation,
so it’s application software. Microsoft SharePoint Designer is an example of application software because it helps you create and publish a Web page or Web site. A business
might use payroll software, collaborative software such as videoconferencing, and inventory management software.
System software handles tasks specific to technology management and coordinates
the interaction of all technology devices. System software includes both operating system software and utility software. Operating system software is system software that
controls your application software and manages how your hardware devices work
together. Popular personal operating system software includes Microsoft Windows,
Mac OS X (for Apple computers), and Linux (an open-source operating system).
There are also operating systems for networks (Microsoft Windows Server is an example),
operating systems for personal digital assistants (Windows Mobile is an example),
and operating systems for just about every other type of technology configuration,
even for refrigerators.
Utility software is software that provides additional functionality to your operating
system software. Utility software includes anti-virus software, screen savers, spam blocker
software, uninstaller software (for properly removing unwanted software), and a host of
other types. Some types of utility software are nice to have, like screen savers, while others
are essential. For example, anti-virus software protects you from computer viruses that
can be deadly for your computer. You definitely need anti-virus software.
This ends our quick tour of technology. In the remainder of this module we’ll explore
categories of computers by size, software in more detail, and hardware in more detail.
Categories of Computers by Size
Computers come in different shapes, sizes, and colours. Some are small enough that you
can carry them around with you, while others are the size of a family refrigerator. Size is
usually related to power and speed, and thus price.
Computer Hardware and Software
A smartphone is a mobile device offering capabilities previously available in a personal
digital assistant (PDA) combined with the ability to use a mobile telephone network,
connect to the internet via WiFi and perhaps even the availability of global positioning
(GPS). One might think of a smartphone as having PC-like functionality. Competition in
this area is fierce, with the two biggest players (Waterloo, Ontario’s RIM and Apple) slugging it out in the market. Despite this high-profile battle, smartphones lack an industry
standard definition. One often-cited characteristic is the ability to run operating system
software that provides a platform for software developers to write applications to run on the
device. Others are satisfied if, in addition to functioning as a telephone, the device offers
features such as e-mail and Internet access, with or without a full QWERTY keyboard.
A tablet PC is a pen-based computer that provides the screen capabilities of a PDA with
the functional capabilities of a notebook or desktop computer. Similar to PDAs, tablet
PCs allow you to use a writing pen or stylus to write notes on the screen and touch the
screen to perform functions such as clicking on a link while visiting a Web site. Tablet
PCs come in two designs—convertibles and slates. Convertible tablet PCs look like
notebook computers, including a screen that you lift up and set in position with a full
keyboard and touch pad underneath. Using a convertible PC, you can swivel the screen
and lay it flat on the keyboard, converting it into a topless notebook that closes.
Figure A.2
Smartphones, Tablet PCs,
and Notebooks
Extended Learning Module A
Slate tablet PCs come without an integrated physical keyboard, making the tablet the
entire computer. You can buy a docking station for a slate tablet PC, giving you the ability
to connect a keyboard and mouse.
A notebook computer is a small, portable, fully functional, battery-powered computer.
Notebooks come equipped with all the technology to meet your personal needs, and
weigh not much more than a kilogram. If you need a fully functional computer in a variety
of places—home, work, school, and/or on the road—then a notebook computer may be
just the answer. Notebook computers range in price from about $600 to several thousand dollars depending on the selected configuration.
Figure A.3
Desktop for Gaming
A desktop computer is the most popular choice for personal computing needs. You can
choose a desktop computer with a horizontal system box (the box is where the CPU, RAM,
and storage devices are held) or choose a desktop computer with a vertical system box
(called a tower) that you usually place on the floor near your work area. Desktop computers
range in price from a little less than $500 to several thousand dollars. Dollar for dollar with
comparable characteristics, a desktop computer is faster and more powerful than a notebook computer. Some desktops are built especially for gaming (see Figure A.3).
Which one you need—PDA, tablet PC, notebook, or desktop computer—is a function of your unique individual needs. PDAs offer great
portability and allow you to keep a calendar, send and receive e-mail, take
short notes, and even access the Web. But they’re not designed to help
you write a term paper, build a Web site, or create a complex graph with
statistical software. For these and more complex tasks, you need a notebook, tablet PC, or desktop computer.
So, the next question is, should you buy a notebook or a tablet PC?
Most likely, you need a computer that supports full word processing,
spreadsheet, presentation, Web site development, and some other
capabilities. You need to decide where you’ll need your computer. If you
need to use your computer both at home and at school (or perhaps at
work), then you should buy one of these because they are, in fact, portable. So, if you’d
like to be able to surf the Web and get e-mail in your hotel room while on a business or
vacation trip, a notebook computer or a tablet PC may be what you need.
Smartphones already allow users to perform “complex” tasks such as creating an elaborate spreadsheet or graph, and even integrating speech recognition. Many offer Global
positioning, access to secure corporate networks, and even interfaces to enterprise software such as SAP. As network capacity and availability (through WiFi) increase, the sky
is the limit for smartphone technology.
PDAs, notebooks, and desktop computers are designed to meet your personal informationprocessing needs. In business, however, many people often need to access and use the
same computer simultaneously. In this case, businesses need computing technologies
that multiple people (perhaps hundreds or even thousands) can access and use at the
same time. Computers of this type include minicomputers, mainframe computers, and
supercomputers (see Figure A.4).
Computer Hardware and Software
A minicomputer (sometimes called a mid-range computer) is designed to meet the
computing needs of several people simultaneously in a small to medium-size business
environment. Minicomputers are more powerful than desktop computers but also cost
more, ranging in price from $5,000 to several hundred thousand dollars. Businesses often
use minicomputers as servers, either for hosting a Web site or as an internal computer on
which shared information and software is placed. For this reason, minicomputers are well
suited for business environments in which people need to share common information,
processing power, and/or certain peripheral devices such as high-quality, fast laser printers.
A mainframe computer (sometimes just called a mainframe) is a computer designed
to meet the computing needs of hundreds of people in a large business environment.
So mainframe computers are a step up in size, power, capability, and cost from minicomputers. Mainframes can easily cost in excess of $1 million. With processing speeds
greater than 1 trillion instructions per second (compared to a typical desktop that can
process approximately 3 billion instructions per second), mainframes can easily handle
the processing requests of hundreds (or thousands) of people simultaneously.
A supercomputer is the fastest, most powerful, and most expensive type of computer.
Universities that are heavily involved in research and “number crunching,” such as
University of Montreal, University of Alberta, and University of New Brunswick, employ
supercomputers because of the speed with which they can process information. Very
large, customer-oriented businesses such as General Motors and AT&T also employ
supercomputers just to handle customer information and transaction processing. Their
business needs require the high level of support and the powerful processing power
provided by supercomputers.
How much do you really need to know about the technical specifics (CPU speed, storage
disk capacity, and so on), prices, and capabilities of minicomputers, mainframe computers,
and supercomputers? Probably not much, unless you plan to major in information
technology. What you should concentrate on is the technical specifics, prices, and
capabilities of PDAs, tablet PCs, notebooks, and desktop computers. These tools will
be your companions for your entire business career. Learn about them and know them
well—on an ongoing basis.
Figure A.4
Mainframes, and
Extended Learning Module A
Software: Your Intellectual Interface
The most important tool in your technology tool set is software. Software contains the
instructions that your hardware executes to perform an information-processing task for
you. So, software is really your intellectual interface, designed to automate processing tasks.
Without software, your computer is little more than a very expensive doorstop. As we’ve
stated, there are two categories of software: application software and system software.
Application software is the software you use to meet your specific information-processing
needs, including payroll, customer relationship management, project management, training, word processing, and many, many others. Application software can be categorized as
either personal productivity software or vertical and horizontal market software.
PERSONAL PRODUCTIVITY SOFTWARE Personal productivity software helps
you perform personal tasks—such as writing a memo, creating a graph, and creating a
slide presentation—that you can usually do even if you don’t own a computer. You’re
probably already familiar with some personal productivity software tools including
Microsoft Word, Microsoft Excel, Firefox, and Quicken (personal finance software).
Three modules in this text help you learn how to use some of these tools—Extended
Learning Module H (for Microsoft Excel, spreadsheet software), and Extended Learning
Module G (for Microsoft Access, database management system). Figure A.5 describes
the 10 major categories of personal productivity software and some of the better
known packages within each category.
VERTICAL AND HORIZONTAL MARKET SOFTWARE While performing organizational processes in your career, you’ll also frequently use two other categories of
application software: vertical market software and horizontal market software.
Vertical market software is application software that is unique to a particular industry.
For example, the health care industry has a variety of application software unique to
that market segment, including radiology software, patient-scheduling software, nursing
allocation software, and pharmaceutical software. Vertical market software is written
specifically for an industry. Health care industry patient-scheduling software wouldn’t
work well for scheduling hair styling and manicure appointments in a beauty salon.
Computer Hardware and Software
Figure A.5
Word processing—Helps you create papers,
letters, memos, and other basic documents
• Microsoft Word
Categories of Personal
Productivity Software
Spreadsheet—Helps you work primarily
with numbers, including performing
calculations and creating graphs
• Microsoft Excel
Presentation—Helps you create and edit
information that will appear in electronic
• Microsoft PowerPoint
Desktop publishing—Extends word
processing software by including design
and formatting techniques to enhance the
layout and appearance of a document
• Microsoft Publisher
Personal information management (PIM)—
Helps you create and maintain (1) to-do
lists, (2) appointments and calendars,
and (3) points of contact
• Microsoft Outlook
Personal finance—Helps you maintain
your cheque book, prepare a budget,
track investments, monitor your credit
card balances, and pay bills electronically
• Quicken Quicken
Web authoring—Helps you design and
develop Web sites and pages that you
publish on the Web
• Microsoft SharePoint Designer
Graphics—Helps you create and edit
photos and art
• Microsoft PhotoDraw
Communications—Helps you communicate
with other people
• Microsoft Outlook
Database management system (DBMS)—
Helps you specify the logical organization
for a database and access and use the
information within a database
• Microsoft Access
* Publisher name given first.
• Corel WordPerfect
• Corel Quattro Pro
• Corel Presentations
• Quark QuarkXPress
• Corel Central
• Microsoft Money
• Macromedia Dreamweaver
• Adobe PhotoShop
• Internet Explorer
• FileMaker FileMaker Pro
Extended Learning Module A
Horizontal market software, on the other hand, is application software that is general
enough to be suitable for use in a variety of industries. Examples of horizontal market
software include
• Inventory management
• Payroll
• Accounts receivable
• Billing
• Invoice processing
• Human resource management
The preceding functions (and many others) are very similar, if not identical, across
many different industries, enabling software publishers to develop one particular piece
of software (e.g., accounts receivable) that can be used by many different industries.
Personal productivity software is actually a type of horizontal market software in that
it is general enough to be suitable for use in a variety of industries. No matter what
industry you work in, you need basic word processing software for creating memos,
business plans, and other basic documents.
There are, however, some key differences between personal productivity software and
horizontal (and vertical) market software. First is the issue of price. You can buy a full
suite of personal productivity software for less than $400. In contrast, some individual
horizontal and vertical market software packages may cost $500,000 or more. Second
is the issue of customizability. When you purchase personal productivity software, you
cannot change the way it works. That is, you’re buying the right to use it but not to
change how it operates. With horizontal and vertical market software you may be able
to purchase the right to change the way the software works. So, if you find a payroll
software package that fits most of your organizational needs, you can buy the software
and the right to change the operation of the software so that it meets your needs precisely.
This is a very common business practice when purchasing and using horizontal and
vertical market software.
In Chapter 6, we discuss how organizations go about the process of developing software
for their particular needs, including how organizations can and do purchase vertical and
horizontal market software and then customize that software.
System Software
System software controls how your various technology tools work together as you use
your application software to perform specific information-processing tasks. System
software includes two basic categories: operating system software and utility software.
OPERATING SYSTEM SOFTWARE Operating system software is system software
that controls your application software and manages how your hardware devices
work together. For example, after using Excel to create a graph, if you choose to print
the graph, your operating system software takes over, ensures that you have a printer
attached and that the printer has paper (and tells you if it doesn’t), and sends your graph
to the printer along with instructions on how to print it.
Your operating system software supports a variety of useful features, one of which is
multitasking. Multitasking allows you to work with more than one piece of software at a
time. Suppose you wanted to create a graph in Excel and insert it into a word processing
document. With multitasking, you can have both pieces of application software open at
the same time, and even see both on the screen. So, when you complete the creation of
Computer Hardware and Software
your graph, you can easily copy and paste it into your word processing document without
having to exit the spreadsheet software and then start your word processing software.
There are different types of operating system software for personal environments
and for organizational environments that support many users simultaneously. The latter,
called network operating systems or NOSs, we explore in Extended Learning Module B
(Network Basics). Popular personal operating systems include
• Microsoft Windows Vista—Microsoft’s latest personal computer operating
system in a wide range of editions including Vista Home Basic, Vista Home
Premium, Vista Business, and Vista Ultimate.
• Microsoft Windows XP Home and XP Professional (Windows XP Pro)—
Microsoft’s predecessor to the Vista personal computer operating system.
Versions are available for home and, with enhanced features, for business users.
• Mac OS X—Apple’s newest operating system.
• Linux—An open-source operating system that provides a rich operating
environment for high-end workstations and network servers.
Open-source software is software for which the source code (how the software was
actually written) is publicly available and free of charge. Unlike commercial software,
open-source software is created and maintained by a distributed network of engineers,
software developers, and users, each making contributions to the software.
The advantages of open-source software are numerous. Because the source code is
available, users of the software may modify it to suit their needs and take comfort in the
fact that changes they wish to make are fully under their control. You can compare this
with commercial, or closed-source, software, for which the customer must go to the vendor
and pay for changes to be made and wait until the vendor has made those changes.
There are many examples of open-source software, including
• (office suite, including word processor, spreadsheet, and
presentation software)
• Apache HTTP Server (Web server)
• Linux (operating system)
• MySQL (open-source DBMS with commercial support).
If you’re considering purchasing a notebook computer that you’ll use extensively
at school connected to a network there, we recommend that you contact your school’s
technology support department to determine which operating system is best for you.
UTILITY SOFTWARE Utility software adds functionality to your operating system
software. Sometimes it is crucial. A simple example is screen saver software (which is
probably also a part of your operating system). The most important utility software is
anti-virus software. Anti-virus software is utility software that detects and removes or
quarantines computer viruses. Viruses are everywhere today, with more than 100 new
ones surfacing each month. Some viruses are benign: they do something annoying like
causing your screen to go blank but do not corrupt your information. Other viruses are
deadly, perhaps reformatting your hard disk or altering the contents of your files. You
definitely need anti-virus software to protect your computer. We talk much more about
this vitally important topic and guarding against possible attacks that can be launched
against your computer from cyberspace in Chapter 8 and Extended Learning Module C
(Computer Crime and Digital Forensics).
Other types of utility software include
• Crash-proof software—Utility software that helps you save information if your
system crashes and you’re forced to turn it off and then back on again.
Extended Learning Module A
• Uninstaller software—Utility software that you can use to remove software from
your hard disk that you no longer want.
• Disk optimization software—Utility software that organizes the information on
your hard disk in the most efficient way.
• Spam-blocker software—Utility software that filters unwanted e-mail from your
inbox. Spam is roughly equivalent to unsolicited telephone marketing calls. The term
spam is said to derive from a famous Monty Python sketch (“Well, we have Spam;
tomato and Spam; egg and Spam; egg, bacon, and Spam ...”) that is still popular.
• Anti-spyware software—Utility software that detects and removes spyware and
other unwanted software that can track every electronic move you make.
You definitely need utility software. Don’t think of utility software as “optional” software
just because it “adds” functionality to your computer. The above examples are just a few
of the many types of utility software you’ll find in a utility software suite, and all are helpful.
Hardware: Your Physical Interface
To properly understand the significant role of your hardware (the physical components
of your computer), it helps to know something about how your computer works. You
work with information in the form of characters (A–Z, a–z, and special ones such as an
asterisk, a question mark, etc.) and numbers (0–9). Computers, on the other hand, work
only with 1s and 0s in terms of what we call bits and bytes. Computers use electricity to
function, and electrical pulses have two states: on and off, which are assigned the values
of 1 and 0, respectively.
What are bits and bytes? A binary digit (bit) is the smallest unit of information that
your computer can process. A bit can either be a 1 (on) or a 0 (off). The technical challenge
is to be able to represent all our natural language characters, special symbols, and numbers
in binary form. ASCII is one agreed-upon standard to do this. ASCII (American
Standard Code for Information Interchange) is the coding system that most personal
computers use to represent, process, and store information. In ASCII, a group of eight
bits represents one natural language character and is called a byte.
For example, if you were to type the word cool on the keyboard, your keyboard (a
hardware device) would change it into four bytes—one byte for each character—that
would look like the following to be used by your computer:
This grouping of 1s and 0s would be used for “cool” as it moves around or is stored
on your computer—as it travels from one device to another, is stored on a storage device,
and is processed by your CPU.
There are three important conclusions that you should draw from this discussion so
far. First, your hardware works with information in a different form (although with the
same meaning) than you do. Second, the term byte is the bridge between people and a
computer. A computer can store one character, special symbol, or number in a byte.
ASCII is but one scheme for interfacing between people and machines. A newer
standard is Unicode. The Unicode Consortium spearheads a drive to adopt Unicode
and its 100,000 character set, with support for character properties, rules for normalization,
decomposition, collation, rendering and bidirectional display order (for the correct
display of text containing both right-to-left scripts, such as Arabic or Hebrew, and leftto-right scripts such as English, French and German.)1
Computer Hardware and Software
Third, the primary role of your input and output devices is to convert information
from one form to another. Input devices convert information from human-readable form
into bits and bytes, while output devices convert the 1s and 0s to something people can
recognize. All other hardware works with bits and bytes.
An input device is a tool you use to enter information and commands. You can use
a keyboard to type in information, for example, and use a mouse to point and click on
buttons and icons. As you saw in the previous section, input devices are responsible for
converting information in human-readable form to the binary code that computers use.
The newest input system is radio frequency ID or RFID for short. Warehouse and logistics applications are now quite common, but a novel and critical application had its start
right here, when Canada became the first country to mandate RFID tags for cattle. The
program allows federal food inspection teams to more effectively monitor and detect the
path of animal diseases such as Bovine Spongiform Encephalopathy (BSE), commonly
known as Mad-Cow Disease.2, 3
Below are the principal types of input devices being used today (see Figures A.6
and A.7).
• Keyboards are the most often used input devices for desktop and notebook
computers, while styluses are the most frequently used input devices for PDAs
and tablet PCs. A stylus is a pen-like device used to write or draw on a PDA
or tablet PC. Keyboards and styluses allow you to input both information and
commands, and both are used in business and personal settings.
Bar Code
Figure A.6
Categories of
Input Devices
Extended Learning Module A
Figure A.7
Common Input Devices
• Pointing devices are devices that are used to navigate and select objects on a
display screen.
• A mouse is a pointing device that you use to click on icons or buttons. The three
types are mechanical (using a ball), optical (using red light), and wireless (using waves).
• A trackball is similar to a mechanical mouse, but it has the ball on top.
• A touchpad is a little rectangle that you use to move the cursor with your finger;
it is often found on notebook computers.
• A pointing stick is a little rod (like a pencil-top eraser) used almost exclusively
on notebook computers.
• Game controllers are used for gaming to better control screen action.
– A gaming wheel is a steering wheel and foot pedals for virtual driving.
– A joystick is a vertical handle with programmable buttons that control action.
– A gamepad is a multifunctional input device with programmable buttons,
thumb sticks, and a directional pad.
• Scanners are used to convert information that exists in visible form into
electronic form.
– An image scanner captures images, photos, text, and artwork that already
exist on paper.
– A bar code scanner reads information that is in the form of vertical bars, where
their width and spacing represent digits (often used in point-of-sale [POS]
systems in retail environments).
– An optical mark reader detects the presence or absence of a mark in a
predetermined spot on the page (often used for true/false and multiple-choice
exam answers).
– An optical character reader reads characters that appear on a page or sales
tag (often used in point-of-sale [POS] systems in retail environments).
Computer Hardware and Software
– A biometric scanner scans some human physical attribute like your
fingerprint or iris for security purposes.
• Digital cameras capture still images or video as a series of 1s and 0s. Some will
capture only stills, others do both.
– Digital still camera—digitally captures still images in varying resolutions.
– Digital video camera—captures video digitally.
– Webcam—captures digital video to upload to the web.
– Microphones capture audio for conversion into electronic form.
An output device is a tool you use to see, hear, or otherwise recognize the results of
your information-processing requests. The most common output devices for both business and personal computing environments are monitors and printers, but speakers and
plotters (printers that generate drawings) are also output devices (see Figure A.8). Any
device that converts the digital form of information in a computer to something that you
can see, read, or hear is an output device.
MONITORS Monitors come in two varieties: CRT or flat-panel displays (see
Figure A.9). CRTs are the monitors that look like traditional television sets, while
flat-panel displays are thin, lightweight monitors that take up much less space than
CRTs. Flat-panel displays are either liquid crystal display or gas plasma display.
Liquid crystal display (LCD) monitors make the screen image by sending electricity
through crystallized liquid trapped between two layers of glass or plastic. Gas plasma
displays send electricity through gas trapped between two layers of glass or plastic to
create a screen image. A gas plasma display usually provides a better image, but is more
expensive than a comparably sized LCD monitor.
Figure A.8
Flat Panel
Gas Plasma
Categories of
Output Devices
Extended Learning Module A
Figure A.9
Monitors Are Common
Output Devices
When selecting a monitor, the important features to consider, besides its price and
physical size, are the monitor’s (1) viewable image size, (2) resolution, and (3) dot pitch.
1. The viewable image size (VIS) is the size of the image. The quoted size (17", 19",
etc.) is measured diagonally from corner to corner. In a flat-panel display, this size
is the same as the distance from corner to opposite corner of the monitor’s frame,
while in a CRT it’s slightly less since the image doesn’t completely fill the screen
area on a CRT. The physical size of a CRT, for a comparable image size, is usually
larger since it’s much deeper than the flat-panel displays.
2. The resolution of a screen is the number of pixels it has. Pixels (picture elements)
are the dots that make up the image on your screen. For example, a monitor with
a resolution of 1,280 × 1,024 has 1,280 pixels across and 1,024 pixels down the
screen. The higher the resolution, the better the image.
3. Dot pitch is the distance between the centres of a pair of like-coloured pixels.
So, a monitor with .24 mm dot pitch is better than one with .28 mm dot pitch
because the dots are smaller and closer together, giving a better quality image.
Printers are another common type of output device (see Figure A.10).
The sharpness and clarity of a printer’s output depend on the printer’s resolution. The
resolution of a printer is the number of dots per inch (dpi) it produces. This is the
same principle as the resolution in monitors. As is the case with monitors, the more dots
per inch, the better the image, and consequently, the more costly the printer. High-end
personal printers usually have a resolution of 1,600 × 1,600 or better. Multiplying these
numbers gives you 2,560,000 dots per square inch. Some printers, especially those that
advertise high-quality photo output, achieve resolutions of 5,760 × 1,440 by making
multiple passes across the image to produce the clarity needed.
Computer Hardware and Software
Figure A.10
• Inkjet printers make images by forcing ink droplets through nozzles. Standard inkjet
printers use four colours: black, cyan (blue), magenta (purplish pink), and yellow.
Some inkjet printers produce high-quality images and are often advertised as photo
printers. These have two shades each of magenta and cyan for a total of six colours.
• Laser printers form images using the same sort of electrostatic process that
photocopiers use. Laser printers are usually more expensive than inkjets, but
they have become dramatically cheaper lately. They usually provide better quality
images than inkjets. They come in black and white and in colour versions.
• Multifunction printers scan, copy, and fax, as well as print. These devices are
very popular in homes and small offices since they offer so many features in one
unit. Multifunction printers can be either inkjet or laser.
• Plotters form their output by moving a pen across the surface of a piece of paper.
Plotters were the first type of printer that could print with colours and render
graphics and full-size engineering drawings. As a rule, plotters are much more
expensive than printers. They are most frequently used for CAE (computer-aided
engineering) applications, such as CAD (computer-aided design) and CAM
(computer-aided manufacturing).
As opposed to RAM, which is temporary memory, storage media don’t lose their contents
when you turn off your computer. The main issues to consider when choosing a storage
medium are (1) whether you want portability, (2) how much storage space you need, and
(3) whether you need to change the information on the medium.
Some storage devices, such as hard disks, offer easy update capabilities and high storage
capacity, but may not be portable. Others, like flash memory devices, while they are portable and updateable, have less storage space. Still others like DVD-ROMs are portable with
high capacity, but the information that comes on them can’t be changed (see Figure A.11).
Capacities of storage media are measured in megabytes, gigabytes, and terabytes.
A megabyte (MB or M or Meg) is roughly 1 million bytes; a gigabyte (GB or Gig) is
roughly 1 billion bytes; and a terabyte (TB) is roughly 1 trillion bytes. A consumer hard
disk would have a capacity of between 1 and 250 gigabytes while a hard disk for a large
organization (also called a hard disk pack) can hold in excess of 100 TB of information.
Common storage devices include
• Magnetic storage media
– A hard disk is a magnetic storage device with one or more thin metal platters
or disks that store information sealed inside the disk drive. You usually get one
installed in your system unit (the computer box) when you buy a computer.
Printers Are Also
Common Output Devices
Extended Learning Module A
Figure A.11
Categories of
Storage Media
Hard Disk
(SD) Card
Flash (CF)
(SM) Card
If you need more hard disk space or want portability, you can get an external
unit that you can plug into a USB port. (We’ll discuss USB ports in a later
section.) A hard disk offers ease of updating and large storage capacity.
• Optical storage media are plastic discs on which information is stored, deleted,
and/or changed using laser light, and include CDs and DVDs, of which there are
several types:
– A CD-ROM (compact disc—read-only memory) is an optical or laser disc on
which information cannot be changed. A CD stores up to 800 MB of information.
– A CD-R (compact disc—recordable) is an optical or laser disc that you can
write to one time only.
– A CD-RW (compact disc—rewritable) is an optical or laser disc on which you
can save, change, and delete files as often as you like.
– A DVD-ROM is a high-capacity optical or laser disc upon which information
cannot be changed. The capacity of a DVD, unlike that of a CD, varies
according to type.
– A DVD-R or DVD+R (DVD—recordable) is a high-capacity optical or laser
disc to which you can write one time only.
– A DVD-RW or DVD+RW is a high-capacity optical or laser disc on which you
can save, change, and delete files.
Computer Hardware and Software
Figure A.12
Common Types
of Flash Memory
• Flash memory comes in two varieties: flash memory device and flash memory cards
(see Figure A.12). A flash memory device (also called a jump drive, a memory key,
or thumb drive) is a flash memory storage device that is small enough to fit on a key
ring and plugs directly into the USB port on your computer. A flash memory card,
on the other hand, has to be inserted into a reader, which in turn plugs into the USB
port. Flash memory cards have high-capacity storage units laminated inside a small
piece of plastic. There are several different types.
– An xD-Picture (xD) card is a flash memory card that looks like a rectangular
piece of plastic smaller than a penny and about as thick, with one edge slightly
curved. xD cards have capacities ranging from 32 to 512 megabytes.
– A secure digital (SD) card and a MultiMediaCard (MMC) are flash memory
cards that look identical to each other (but SD cards have copy protection built
in), are a little larger than a quarter, and are slightly thicker than a credit card.
– A CompactFlash (CF) card is a flash memory card slightly larger than a toonie
with capacity of up to 6 gigabytes.
– A SmartMedia (SM) card is a flash memory card a little longer than a CF card
and about as thick as a credit card with a capacity of up to 512 megabytes.
– A memory stick media card is an elongated flash memory card about the
width of a penny developed by Sony with a capacity up to 1 gigabyte.
Together, your CPU and RAM make up the real brains of your computer (see Figure A.13).
Your CPU largely determines the power (and also the price) of your computer. The
central processing unit (CPU) is the hardware that interprets and executes the system
and application software instructions and coordinates the operation of all other hardware.
Random access memory (RAM) is a temporary holding area for the information you’re
working with as well as the system and application software instructions that the CPU
currently needs.
Figure A.13
Extended Learning Module A
You’ll often hear the CPU referred to as a microprocessor or a CPU chip. The dominant
manufacturers of CPUs include Intel (with its Celeron, Pentium, and Xeon series for
personal computers) and AMD (with its Athlon and Opteron series). As a consumer,
you’ll probably find the most useful information about CPUs is their relative speeds.
Today’s CPU speed is usually quoted in gigahertz. Gigahertz (GHz) is the number
of billions of CPU cycles per second that the CPU can handle. The more cycles per second, the faster the processing and the more powerful the computer. Gigahertz refers to
how quickly the CPU can carry out the steps it takes to execute software instructions—a
process sometimes called the CPU cycle or machine cycle. A CPU cycle (machine cycle)
consists of retrieving, decoding, and executing the instruction, then returning the result
to RAM. When you load (or open) a program, you’re telling your computer to send a
copy of the program from the storage device (hard disk or CD) into RAM. In carrying
out the software instructions, the CPU repeatedly performs machine cycles as follows:
1. Retrieve an instruction: The control unit, which is the component of the CPU
that directs what happens in your computer, sends to RAM for instructions and
the information it needs. If the instruction says to add 4 and 6, for example, the
two numbers travel as information with the add instruction. The instruction
travels from RAM on the system bus. The system bus consists of electrical
pathways that move information between basic components of the motherboard,
including between RAM and the CPU. When the instruction reaches the CPU it
waits temporarily in CPU cache, which is a type of memory on the CPU where
instructions called up by the CPU wait until the CPU is ready to use them. It
takes much less time to get the instruction from CPU cache to the control unit
than from RAM, so CPU cache speeds processing.
2. Decode the instruction: The CPU gets the instruction out of cache and examines
it to see what needs to be done, in this case, add 4 and 6.
3. Execute the instruction: The CPU then does what the instruction says to do. In
our example, it sends the two numbers to the arithmetic logic unit to be added.
The arithmetic logic unit (ALU) is a component of the CPU that performs
arithmetic, as well as comparison and logic operations.
4. Store the result in RAM: The CPU then sends the result of the addition, 10, to
RAM. There’s not always a result to send back to RAM. Sometimes the CPU
does intermediate calculations that don’t get saved.
You’ll sometimes hear the CPU speed referred to as the “clock speed.” This refers to
the CPU clock. Every CPU has its own CPU clock, which is simply a sliver of quartz that
beats at regular intervals in response to an electrical charge. The beat of the CPU clock
is like the drummer in a marching band. Just as the drummer keeps everyone marching
in time, the CPU clock keeps all your computer’s operations synchronized. Each beat or
tick of the CPU clock is called a clock cycle and is equivalent to a CPU cycle (machine
cycle). The CPU uses the CPU clock to keep instructions and information marching
through your CPU at a fixed rate.
RAM is a sort of whiteboard that your CPU uses while it processes information and
software instructions. When you turn off your computer, everything in RAM disappears—
that’s why we call it “temporary.” When you first start your computer, system instructions
that are necessary to keep your computer running get written into RAM. Then, as you
open applications, like Microsoft Word or Excel, the instructions to make those programs
run join the operating system in RAM. As you type in your document or enter information
into your workbook, that too is stored in RAM. When you’ve finished your work and
save it, a copy is transferred from RAM to your disk or CD.
Computer Hardware and Software
The most important thing you need to know about RAM is its capacity for storing
instructions and information. RAM capacity is expressed in megabytes or gigabytes.
You’ll remember that a megabyte is roughly 1 million bytes. A byte is equivalent to a
character. So RAM with a capacity of 256 megabytes can hold 256 million characters—
that includes operating system instructions as well as the applications and information
that you’re currently using.
NOTEBOOK COMPUTER CPUS AND RAM A notebook computer is to a desktop
computer as a recreational vehicle is to a traditional home—everything is smaller, and
power to run devices is limited since you have to carry the power sources with you. A
mobile CPU is a special type of CPU for a notebook computer that changes speed, and
therefore power consumption, in response to fluctuation in use. A desktop CPU, running
at 1 GHz, uses between 75 and 1,090 watts of power whereas a mobile CPU might run at
a much smaller 34 watts. RAM modules for notebook computers are smaller than those
for desktop computers.
Since the CPU controls all computer hardware, all hardware devices must be connected
to the CPU, just as your limbs are connected to your brain through your spinal cord.
The CPU, along with RAM, is located on the large circuit board (called the motherboard) inside your system unit. The connector (or plug) on the end of the cable coming
out of your printer connects it to the motherboard, which then carries information
between the CPU and the printer.
WIRED CONNECTIONS All devices that are not wireless have connectors on the ends
of cables that plug into ports on the computer. A port is the place on your system unit,
monitor, or keyboard through which information and instructions flow to and from your
computer system. For wired connections it’s the opening or socket where you insert the
connector, and for wireless devices a port is where the wave information goes in and out.
The ports are accessible on the outside of the system unit, which means that you
don’t have to open up the system unit to plug in your scanner. There are various types of
connectors/ports (see Figure A.14) including
• USB (universal serial bus) ports, which fit small, flat plug-and-play, hot-swap
USB connectors. Using USB hubs, you can connect up to 127 devices to a single
USB port on your computer. Hot swap is an operating system feature that allows
you—while your computer is running—to unplug a device and plug in a new
one (without first shutting down your computer). Plug and play is an operating
feature that finds and installs the device driver for a device that you plug into
your computer. USB connectors/ports come in two speeds: USB 1.1 and USB 2.0
(which is faster), and in two physical shapes called Type A and Type B, respectively.
Type A USB connectors/ports are all the same size and shape, but Type B USB
connectors are smaller, squarer, and come in several different sizes. Type B connectors
are usually on the end of the cable that plugs into the device (like a digital camera).
• Firewire ports (also called IEEE 1394 or I-Link) fit hot-swap, plug-and-play
Firewire connectors, and you can connect up to 63 Firewire devices to a single
Firewire port by daisy-chaining the devices together.
– Serial connectors/ports are gradually being replaced by USB and Firewire.
• PS/2 ports fit PS/2 connectors, which you often find on keyboards and mice.
PS/2 is a special type of serial connector/port.
Extended Learning Module A
Figure A.14
Categories of Connectors
and Ports
Hot Swap
Plug and Play
USB 1.1
USB 2.0
– A standard video-out conenctor is included with all PCs and laptops to drive
an external display. However, video cards now often include two connectors to
allow dual monitor viewing. Several standards exist.
• Parallel ports fit parallel connectors, which are large, flat connectors found almost
exclusively on printer cables, but that are losing popularity in favour of USB.
Figure A.15 provides photo illustration of many of the ports and connectors we’ve
just described.
Wireless devices transfer and receive information in
the form of waves, either infrared or radio. Different types of waves have different
frequencies. The three types most frequently used in personal and business computer
environments are infrared, Bluetooth, and WiFi.
• Infrared, also called IR or IrDA (infrared data association), uses red light to
send and receive information. Infrared light has a frequency that’s below what the
eye can see. It’s used for TV remotes and other devices that operate over short
distances (the effective distance is about one mile) that are free of obstacles.
• Bluetooth is a standard for transmitting information in the form of short-range
radio waves over distances of up to 30 feet and is used for purposes such as
wirelessly connecting a cell phone or a PDA to a computer.
• WiFi (wireless fidelity) is a standard for transmitting information in the form of
radio waves over distances up to about several miles. WiFi has several forms. For
example, WiFi is also called IEEE 802.11a, b, or g, each of which is a unique type.
WiFi is usually the type of wireless communication used in a network environment.
EXPANSION CARDS AND SLOTS Whether wired or wireless, ports are sometimes
directly on the motherboard and sometimes on expansion cards. An expansion card (or
board) is a circuit board that you insert into the expansion slot (a long skinny socket)
Computer Hardware and Software
Serial connector
Firewire connector
Parallel connector
Ethernet connector
Figure A.15
USB connector
on the motherboard and to which you connect a peripheral device. Information coming
from and going to expansion slots and ports moves along wires (called a “bus”) to the
CPU. The expansion bus is the set of pathways along which information moves between
devices outside the motherboard and the CPU. We have already discussed the system
bus that moves information between basic motherboard components, including RAM
and the CPU.
To add devices to your notebook computer, you slide a PC card into the PC card slot
on the notebook, and connect the device to the PC card. A PC card (which is an updated
version of the traditional PCMCIA card) is the expansion card you use to add devices
to your notebook computer. PC cards look like thick credit cards. PC card slots are the
openings, one on top of the other, on the side or front of a notebook, where you connect
external devices with a PC card. For example, if you wanted to add a CD-ROM drive,
you’d slide a PC card into the slot and then connect the CD-ROM drive to the connector on
the PC card. One of the great things about PC cards is that you can hot-swap devices.
Ports and Connectors to
Connect Devices to the
CPU on the Motherboard
Extended Learning Module A
LO1 Define information technology (IT) and its
two basic categories: hardware and software.
Information technology (IT) is any computerbased tool that people use to work with
information and support the information and
information-processing needs of an organization.
For example, IT includes cell phones, PDAs,
software such as spreadsheet software, and
output devices such as printers. Hardware
consists of the physical devices that make up
a computer (often referred to as a computer
system). Software is the set of instructions that
your hardware executes to carry out a specific
task for you.
LO2 Describe the categories of computers based
on size. Categories of computers by size include
personal digital assistants, tablet PCs, notebook
computers, desktop computers, minicomputers,
mainframe computers, and supercomputers.
A personal digital assistant (PDA) is a small
handheld computer that helps you surf the
Web and perform simple tasks such as note
taking, calendaring, appointment scheduling,
and maintaining an address book. A tablet
PC is a pen-based computer that provides the
screen capabilities of a PDA with the functional
capabilities of a notebook or desktop computer.
A notebook computer is a small, portable, fully
functional battery-powered computer designed
to carry around. A desktop computer is the most
popular choice for personal computing needs.
These four are all computers designed for use
by one person. A minicomputer (mid-range
computer) is designed to meet the computing
needs of several people simultaneously in a
small to medium-size business environment.
A mainframe computer (mainframe) is a
computer designed to meet the computing
needs of hundreds of people in a large business
environment. A supercomputer is the fastest,
most powerful, and most expensive type of
computer. In the order given, PDAs are the
smallest, least powerful, and least expensive while
supercomputers are the largest, most powerful,
and most expensive.
LO3 Compare the roles of personal productivity,
vertical market, and horizontal market software.
Application software executes your specific
programs and tasks. Personal productivity
software helps you perform personal tasks—such
as writing a memo, creating a graph, and creating
a slide presentation—that you can usually do even
if you don’t own a computer. Vertical market
software is application software that is unique to a
particular industry. Horizontal market software
is application software that is general enough to be
suitable for use in a variety of industries. Personal
productivity software is very inexpensive when
compared to both vertical market and horizontal
market software. With personal productivity
software, you do not obtain the right to change the
way the software works. If you buy vertical market
or horizontal market software, you can often buy
the right to change the way the software works.
LO4 Describe the roles of operating system software
and utility software as components of system
software. System software handles technology
management tasks and coordinates the interaction
of all your technology devices. Operating system
software controls your application software
and manages how your hardware devices work
together. So operating system software really
enables you to run application software. Utility
software adds additional functionality to your
operating system, including such utilities as
anti-virus software, screen savers, crashproof software, uninstaller software, disk
optimization software, spam blocking software,
and anti-spyware software. Although these
“add” functionality, you definitely need utility
software, especially anti-virus software.
LO5 Define the purpose of each of the six major
categories of hardware. The six major categories
of hardware are
• Input devices, which convert information and
commands from a form that you understand
into a form your computer can understand.
Computer Hardware and Software
• Output devices, which help you see, hear,
or otherwise accept the results of your
information-processing requests, that is,
convert information from a form your computer
understands into a form you can understand.
• CPU and RAM, which are the real brains
of your computer; they execute software
instructions (CPU) and hold the information,
application software, and operating system
software you’re working with (RAM).
• Storage devices, which store information for
use at a later time.
• Telecommunications devices, which send
information to and from persons and locations.
• Connecting devices, which connect all your
hardware devices to each other.
Key Terms and Concepts
Anti-spyware software, 294
Anti-virus software, 293
Application software, 286
Arithmetic logic unit (ALU), 302
ASCII (American Standard
Code for Information
Interchange), 294
Bar code scanner, 296
Binary digit (bit), 294
Biometric scanner, 297
Bluetooth, 304
Byte, 294
CD-R (compact disc—recordable),
CD-ROM (compact disc—read-only
memory), 300
CD-RW (compact disc—rewritable),
Central processing unit (CPU), 286
Communications software, 291
CompactFlash (CF) card, 301
Control unit, 302
CPU cache, 302
CPU clock, 302
CPU (machine) cycle, 302
Crash-proof software, 293
CRT, 297
Database management system
(DBMS), 291
Desktop computer, 288
Desktop publishing software, 291
Digital camera, 297
Digital still camera, 297
Digital video camera, 297
Disk optimization software, 294
Dot pitch, 298
recordable), 300
DVD-ROM, 300
DVD-RW or DVD+RW, 300
Expansion bus, 305
Expansion card (board), 305
Expansion slot, 304
Firewire port (IEEE 1394 or
I-Link), 303
Flash memory card, 301
Flash memory device, 301
Flat-panel display, 297
Game controller, 296
Gamepad, 296
Gaming wheel, 296
Gas plasma display, 297
Gigabyte (GB or Gig), 299
Gigahertz (GHz), 302
Graphics software, 291
Hard disk, 293
Hardware, 284
Horizontal market software, 292
Hot swap, 303
Image scanner, 296
Information technology (IT), 284
Infrared, IR, or IrDA (infrared
data association), 304
Inkjet printer, 299
Input device, 286
Joystick, 296
Keyboard, 295
Laser printer, 299
Linux, 293
Liquid crystal display (LCD)
monitor, 297
Mac OS, 293
Mainframe computer (mainframe),
Megabyte (MB or M or Meg), 299
Memory stick media card, 301
Microphone, 297
Microsoft Windows XP Home, 293
Microsoft Windows XP
Professional (Windows
XP Pro), 293
Microsoft Windows Vista, 293
Minicomputer (mid-range
computer), 289
Mobile CPU, 303
Mouse, 296
Multifunction printer, 299
MultiMediaCard (MMC), 301
Multitasking, 292
Notebook computer, 288
Open-source software, 293
Operating system software, 286
Optical character reader, 296
Optical mark reader, 296
Optical storage media, 300
Output device, 286
Parallel port, 304
PC card, 305
PC card slot, 305
Personal digital assistant (PDA), 287
Personal finance software, 291
Personal information management
software (PIM), 291
Personal productivity software, 290
Pixels (picture elements), 298
Plotter, 299
Plug and Play, 303
Pointing device, 296
Pointing stick, 296
Port, 303
Presentation software, 291
PS/2 port, 302
Random access memory (RAM), 286
Resolution of a printer, 298
Resolution of a screen, 298
Scanner, 296
Secure Digital (SD) card, 301
Extended Learning Module A
SmartMedia (SM) card, 301
Smartphone, 287
Software, 284
Spam blocker software, 294
Spreadsheet software, 291
Storage device, 286
Stylus, 287
Supercomputer, 289
System bus, 302
System software, 286
Tablet PC, 287
Telecommunications device, 286
Terabyte (TB), 299
Touchpad, 296
Trackball, 296
Uninstaller software, 294
USB (universal serial bus) port, 303
Utility software, 286
Vertical market software, 290
Viewable image size (VIS), 298
Web authoring software, 291
Webcam, 297
WiFi (wireless fidelity, or IEEE
802.11a, b, or g), 304
Word processing software, 291
xD-Picture (xD) card, 301
Short-Answer Questions
1. What are the two categories of information
technology (IT)?
2. What are the six categories of hardware?
3. What is the difference between application
software and system software?
4. Dollar for dollar with comparable
characteristics, which is faster and more
powerful—a desktop computer or a notebook
5. What is the difference between vertical and
horizontal market software?
6. What do the terms bit and byte mean?
7. What is a gaming wheel and how does it differ
from a gamepad?
8. What is the difference between a CRT and a
flat-panel display?
9. How would you measure the size of a screen?
10. How is the resolution of a printer comparable
to the resolution of a screen?
11. How does a CD differ from a floppy disk?
12. What are three types of flash memory cards?
13. What is a mobile CPU?
14. Which wireless standard is used by networks?
Assignments and Exercises
SYSTEMS Computers come in varying sizes
and levels of power and performance. Use
the Web to find out about computer system
configurations. Do some comparison shopping
for three types of computers: desktops,
notebooks, and tablet PCs. Choose three Web
sites that sell computer systems. From each
of these sites, choose the most expensive and
least expensive computer systems you can
find for each of the three types of computers.
Create a table for each of the three types of
computers and compare them based on the
following criteria:
Type and speed of CPU
Type and speed of RAM
Amount of CPU cache
System bus speed
Hard disk capacity and speed (revolutions
per minute or rpm)
• Number and type of ports.
the great things about the Web is the number
of e-tailers offering a variety of products and
services. One such e-tailer is Dell, which allows
you to customize and buy a computer. Connect
to Dell’s site at Go to the portion
of Dell’s site that allows you to customize
either a notebook or desktop computer.
First, choose an already-prepared system and
note its price and capability in terms of CPU
speed, RAM size, monitor quality, and storage
capacity. Now, customize that system to
increase CPU speed, add more RAM, increase
monitor size and quality, and add more
storage capacity. What’s the difference in
price between the two? Which system is more
in your price range? Which system has the
speed and capacity you need?
Computer Hardware and Software
SOFTWARE Software instructions on how to
open Microsoft Word or send information to
a printer must be provided to a computer in
great detail and with excruciating accuracy.
Writing code to make the computer execute
these instructions properly and in the right
order is not a simple task. To understand how
detailed you must be, pick a partner for this
project and envision that you are standing in
a kitchen. The task for one of you is to write
down all the instructions that are necessary
to make a peanut butter and jelly sandwich.
When the instructions are complete, have the
other person follow those instructions exactly.
How successful was the second person in
making the sandwich? Did your instructions
include every single step? If not, what did you
leave out?
certainly live in a “multimedia” society, in
which it’s often easy to present and receive
information using a variety of (multi)
media. Presentation tools such as Microsoft’s
PowerPoint can help you easily build
presentations that include audio, animation,
and video. And this may help you get a
better grade in school. Using your preferred
presentation software, document the steps
necessary to add a short audio or video clip to
a presentation. How does the representation
of the clip appear on a slide? How can you
initiate it? Does your presentation software
include any clips that you can insert or do you
have to record your own? Now, try recording a
short audio clip. What steps must you perform?
market is a ferocious, dynamic, and uncertain
one. One of the uncertainties is what operating
system for smartphones will become the
dominant one (if any). For notebooks and
desktops right now, you’re pretty well limited
to the Microsoft family unless you buy an
Apple computer (in which case your operating
system is Mac OS X) or want to venture into
using Linux (which we wouldn’t recommend
for most people). Do some research on the
more popular smartphones available today.
What are the different operating systems?
What different functionality do they offer?
Are they compatible with each other? Take a
guess—which one will come out on top?
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