close

Вход

Забыли?

вход по аккаунту

код для вставкиСкачать
Computers: Tools for an
Information Age
Chapter 1
Objectives
• Describe the three fundamental characteristics of
computers
• Describe at least four areas of society in which computers
are used
• Identify the basic components of a computer system:
input, processing, output, and storage
• List some common input, output, and storage media
• Distinguish data from information
• Describe the significance of networking
• Explain the significance of the Internet
• Explain the various classifications of computers
Contents
•
•
•
•
•
•
Information Age
Computer Literacy
Where Computers Are Used
Computer System
Network
Classifications of Computers
Information Age
• Evolving more rapidly than Industrial Age
• Will continue into the current century
Cornerstones of our Economy
Forging a Computer-Based Society:
•
•
•
•
Land
Labor
Capital
Information
Jobs
Forging a Computer-Based Society:
• From physical to
mental
• From muscle-power to
brain-power
A Computer in Your Future
• Where used?
– Bank withdrawal
– Supermarket
– Drive the car
• Do I need a Personal Computer?
– Half of Americans have one at home
– Many more use at work
• Will I use a computer in my future career?
– Almost every job will involve use of a computer
Computer Literacy
• Awareness
– Importance
– Versatility
– Pervasiveness in our society
• Knowledge
– What are computers
– How do computers work
– Terminology
• Interaction
– Use some simple computer applications
The Nature of Computers
Characteristics
Results
• Speed
• Reliability
• Storage capability
• Productivity
• Decision making
• Cost reduction
Where Computers Are Used
Graphics
Graphs and charts
Animated graphics
Visual walk-through
Where Computers Are Used
Education
• Teaching and
testing aid
• Learning by doing
• Computer-based
instruction
Where Computers Are Used
Retailing
• Bar codes for pricing
and inventory
• Shipping
Where Computers Are Used
Energy
• Locate oil, coal, natural gas, and uranium
• Monitor the power network
• Meter reading
Where Computers Are Used
Law Enforcement
• National
fingerprint files
• National files on
criminal
• Computer
modeling of DNA
Where Computers Are Used
Transportation
• Cars
• Run rapid transit systems
• Load containerships
• Track railroad cars
• Monitor air traffic
Where Computers Are Used
Money
• Record keeping
• Banking by phone
• Credit cards
Where Computers Are Used
Agriculture
• Billing
• Feed combinations
• Crop information
• Livestock breeding and
performance
Where Computers Are Used
Government
• Forecast weather
• Manage parks
• Process immigrants
• Social Security benefits
• Taxes
Where Computers Are Used
The Home
•
•
•
•
•
Educational tool
Record keeping
Letter writing
Budgeting
Drawing and editing
pictures
• Newsletters
• Connecting with others
Where Computers Are Used
Health and Medicine
• Monitor patients
• Electronic imaging
• Diagnose illnesses
Where Computers Are Used
Robotics
• Perform jobs that are dangerous for
humans
• Factory work
Where Computers Are Used
The Human Connection
• Assist the disabled
• Assist athletes by
monitoring their
movements
Where Computers Are Used
The Sciences
Connectivity
• Research
• Simulation
• Communication
• Telecommuting
Where Computers Are Used
Training
Paperwork
• Airline pilots
• Railroad
engineers
• Junk mail
• Term paper
• Record keeping
Computers are all around!
•
•
•
•
•
Grocery store
School
Library
Bank
Mail
We interact with computers everyday!
Computer System
People
Software
Hardware
People
• Computer programmer – person who
writes programs
• Users or End-users – make use of the
computer’s capabilities
Software
• Programs
• Set of instructions that directs the
hardware to do a required task
and produce the desired results
Hardware
Basic Components of a
Computer
Computer
• A machine that can be programmed to
accept data (input), process it into
useful information (output), and store it
away (in secondary storage device) for
safekeeping or later reuse
• Process is directed by software but
performed by the hardware
Function of Computer System
Data handling
I
P
O
S
Input
Process
Output
Storage
Input devices
• Accept data or commands and convert
them to electronic form
• Getting data into the computer
– Typing on a keyboard
– Pointing with a mouse
– Scanning with a wand reader or bar-code
reader
– Terminal
Output devices
• Convert from electronic form to some other
form
• May display the processed results
• Usable information
Monitor or screen
Printer
•
•
•
•
•
•
• Black and white
• Color
Text
Numbers
Symbols
Art
Photographs
Video
The Processor
Central Processing Unit (CPU)
• Converts data to useful information
• Interpret and execute instructions
• Communicate with input, output and
storage
Two Types of Storage
• Secondary storage
long-term storage
• Primary storage or memory
temporary storage
Memory / Primary Storage
• Temporary storage
• Holds input to be processed
• Holds results of processing
• Contains the programs to control the
computer and manipulate input into
output
• Volatile
Secondary Storage
• Long-term storage
• Non-volatile
Secondary Storage Examples
• Magnetic disks – read and written by
magnetic disk drive
– Hard disk
– Diskette
• Optical disks – read and written by optical disk
drives
– CD-ROM
– DVD-ROM
• Magnetic tape – read and written by magnetic
tape drives
– Primarily used for back-up
Computer System
• Computer
– CPU
– Memory
• Peripheral equipment
– Connected to the computer by a cable
– Input, output, storage
Network
• Definition
– A system that uses communications equipment
to connect computers and their resources.
• Types
– Local area network (LAN) – connects computers
in close proximity
– Metropolitan are network (MAN) – connect
computers between buildings in the same
geographic area
– Wide are network (WAN) – connects computers
over great distances
Home Connectivity
• Connect home PC to other computers
• Use modem to convert signals
between electronic (computer) and
analog (voice) formats
Internet
•
•
•
•
Collection of networks
No ownership
No central source for services available
No comprehensive index of what information
is available
Connects Everyone!
Individuals
Businesses
Organizations
Libraries
Research labs
Government
Getting Connected
• User’s computer must connect to a server
• Server must communicate using TCP/IP
• The user can purchase access to a server
from an ISP (Internet Service Provider)
Internet – What Can You Do?
• WWW – World Wide Web
• FTP – File Transfer Protocol
• E-mail
• UseNet
• IRC – Internet Relay Chat
• Bulletin Boards
World Wide Web
• Browser – program that allows the user
to move around and explore the
Internet
• Use the mouse to point and click on
text and graphics
• Web page
• Web site
• Home page
Classifications of Computers
• Use the computer that fits your needs
• Based upon
– Size
– Speed
– Cost
– Portability
– Number of simultaneous users supported
– Available software
– Typical use
Personal Computers
• Other names
– PC
– Microcomputer
– Home computer
• Categories
– Low-end functional
– Fully powered
– Workstations
– Net computer or net box (Web TV)
• Desktop Models
Notebook Computers
• Portable
– Lightweight
– Fits in a briefcase
– Battery operated
• Laptop
– Larger
– Heavier
• More expensive that desktop models
Handheld Computers
• Personal Digital Assistant (PDA)
– Scheduling
– Addresses
– Handwritten input
– May offer wireless e-mail and fax
• Pocket
– More power than PDA
– Runs basic productivity software
Other Types of Computers
Mainframes
–
–
–
–
–
High speed
More expensive
Used to process large amounts of data quickly
Support multiple users
Does server tasks
Supercomputers
– Fastest speed
– Most expensive
1/--страниц
Пожаловаться на содержимое документа