Chapter 1 Our Digital World
Chapter 1
Our Digital World
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Presentation Overview
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Immersed in Digital Technology
The Computer Advantage
How Computers Work
Computers and Computer Systems
Components of a Computer System
Categories of Computers
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Immersed in Digital Technology
Digital
– Refers to an electronic signal that is processed,
sent, and stored as bits.
– Bits are represented by “on” and “off” states
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Immersed in Digital Technology
How has digital technology infiltrated your
daily life?
– Computer technology powers HDTVs,
microwave ovens, watches, cell phones, and
automobiles.
– Embedded chips, computers, networks, and the
Internet and WWW enable us to communicate
globally.
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Immersed in Digital Technology
A computer is an electronic device that
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operates under a set of instructions
accepts data that a user supplies
manipulates data according to a program
produces results
stores the results
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The Computer Advantage
Speed
– Computers operate with lightning-like speed.
– PCs execute billions of program instructions in
one second.
– Supercomputers execute trillions of
instructions per second, the kind of processing
required to forecast the weather and monitor
space shuttle flights.
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The Computer Advantage
Accuracy
– Computers are accurate when accurate
programs and data are entered.
– If inaccurate programs and/or data are entered
(garbage in), the output will also be inaccurate
(garbage out) – GIGO.
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The Computer Advantage
Versatility
– Families use computers for entertainment,
communications, budgeting, online shopping,
homework, playing games, and listening to
music.
– Universities, government agencies, hospitals,
and scientific organizations conduct lifeenhancing research using computers.
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The Computer Advantage
Versatility
– Banks conduct money transfers, account
withdrawals, and payment of checks via
computer.
– Retailers process sales transactions and check
availability of products.
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The Computer Advantage
Versatility
– Manufacturers manage their entire production,
warehousing, and selling processes.
– Schools keep records, conduct distancelearning classes, schedule events, and analyze
budgets.
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The Computer Advantage
Storage
– Computers accept and
store programs and
data.
– Users can access a
program again and
again to process
different data.
– Computers store huge
amounts of data in tiny
physical spaces.
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The Computer Advantage
Communications
– Networks using special equipment and
programs allow computers to communicate
with each other through telephone lines, cable
connections, and satellites.
– Users can exchange information over wireless
networks using personal digital assistants
(PDAs), notebook computers, cell phones, and
pagers.
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The Computer Advantage
Communications
– A local area network (LAN) is a network
confined to a small geographic area, such as a
building, factory, or college campus.
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The Computer Advantage
Communications
– A wide area network (WAN) spans a large
geographical area and might connect a
company’s manufacturing plants dispersed
throughout the United States.
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The Computer Advantage
Communications
– The Internet is a
worldwide network of
large and small
networks linked
together via
communications
hardware, software,
and media for the
purpose of
communicating and
sharing information.
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The Computer Advantage
Communications
– The Internet is used for various purposes,
including
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Sending and receiving messages
Researching information
Buying and selling products and services
Taking online college courses
Accessing entertainment
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The Computer Advantage
Communications
– World Wide Web – a system of linked
computer networks that allows users to move
from one site to another by way of links on
Web pages
– Web page – an electronic document stored on a
computer running the Web site
– Search engine – a software program that
locates and retrieves requested information
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The Computer Advantage
What advantages do computers offer?
– They provide speed, versatility, storage, and
communications.
– They can be used in homes, the workplace, and
society.
– They can be used to communicate, manage
finances, analyze data, plan, research, and for
hundreds of other purposes.
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How Computers Work
Types of Data
– Text data – letters, numbers, and special
characters
– Graphic data – photographs, charts, and
drawings
– Audio data – voice and music
– Video data – moving pictures and images
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How Computers Work
Combining types of data can improve the
presentation quality of a message.
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How Computers Work
During the information processing cycle, data is entered
into a computer, processed, sent as output, and stored (if
required for future use).
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Computers and
Computer Systems
A personal computer
system includes
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The system unit
Input devices
Output devices
Storage devices
Communications
devices
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Components of a Computer
System
Parts of a Personal Computer System
– The system unit – the electronic components
process data into info
– Input devices – allow users to enter
instructions, data, and commands into
computers (keyboard, mouse, microphone)
– Output devices – make information available
to the user (display screen, printer)
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Components of a Computer
System
Parts of a Personal Computer System
– Storage devices – provide for permanent
storage of programs, data, and information
– Communications devices – allow a user to
exchange instructions, data, and information
with other computer users
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Components of a Computer
System
What is the difference between a computer
and a computer system?
– A computer is the part of the system that
processes the data into information.
– A computer system includes the computer
along with input, output, storage, and
communication devices.
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Categories of Computers
Personal Computers
– Fit on a desk, in a
briefcase, or are worn
– Execute 600 million to
three billion
instructions per second
– Are used by a single
user or as part of a
network
– Cost a few hundred to
thousands of dollars
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Categories of Computers
Handheld Computers
– Fit in a hand or are
carried in a pocket
– Execute a few hundred
instructions per second
– Are used by a single
user or as part of a
network
– Cost $99 to a few
hundred dollars
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Categories of Computers
Workstations
– Are similar in size to
desktop PCs
– Execute three to five
billion instructions per
second
– Are used by a single
user or as part of a
network
– Cost a few thousand
dollars
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Categories of Computers
Midrange Servers
– Fit into a large cabinet
– Execute billions of
instructions per second
– Are used by hundreds
of users at the same
time
– Cost $5,000 to
hundreds of thousands
of dollars
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Categories of Computers
Large Servers or
Mainframes
– Occupy a full or partial
room
– Execute billions of
instructions per second
– Are used by hundreds
of thousands of users at
the same time
– Cost several thousands
to millions of dollars
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Categories of Computers
Supercomputers
– Occupy a full room
– Execute trillions of
instructions per second
– Are used by thousands
of users at the same
time
– Cost several million
dollars
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Categories of Computers
What are the basic categories of computers
and their distinguishing characteristics?
– Personal computer – self-contained, capable
of input, processing, output, and storage
– Handheld computer – fits comfortably in a
user’s hand
– Workstation – high-performance single-user
computer
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On the Horizon
Based on the information presented in this
chapter and your own experience, what do
you think is on the horizon?
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