Transcript computer

Unit 1
Introduction to Computing
CSC 110 - Introduction to Computing
Learning Objectives
At the end of this learning unit, you will be able to
• Describe computer systems.
• Identify computer hardware and software.
• List the main functions of operating systems.
• List the main functions of Windows 8 operating
system.
• Discuss computer ethical issues.
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Computer Concepts
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What Is a Computer?
• A computer is an electronic device, operating
under the control of instructions stored in its own
memory
Collects
data
(input)
Processing
Produces
information
(output)
Information Processing Cycle
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Understanding Computer Systems
• Computer system
– Combination of all the components required to process and
store data using a computer
• Hardware
– Equipment associated with a computer
• Software
– Computer instructions: tell the hardware what to do
– Programs: instructions written by programmers
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Computer Systems: Hardware
• Computer hardware components are the physical
pieces of the computer.
• The major hardware components of a computer
are:
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The central processing unit (CPU)
Main memory
Secondary storage devices
Input and Output devices
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Computer Systems: Hardware
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Computer Systems: Hardware
Central Processing Unit
CPU
Instruction (input)
Arithmetic
Logic
Unit
Result (output)
Control
Unit
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Computer Systems: Hardware
Main Memory
• Commonly known as random-access memory (RAM)
• RAM contains:
– currently running programs
– data used by those programs.
• RAM is divided into units called bytes.
• A byte consists of eight bits that may be either on or
off, or 1 or 0.
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Computer Systems: Hardware
Main Memory
• A bit is either on or off:
1
1
1
1
– 1 = on
– 0 = off
0
0 0
0
• The bits form a pattern that represents a character or
a number.
• Each byte in memory is assigned a unique number
known as an address.
• RAM is volatile, which means that when the
computer is turned off, the contents of RAM are
erased.
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Computer Systems: Hardware
Secondary Storage Devices
• Secondary storage devices are capable of storing
information for longer periods of time (non-volatile).
• Common Secondary Storage devices:
• Disk drive
• External drive
• CD drive
• Solid state drive
• USB drive
• DVD drive
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Computer Systems: Hardware
Input Devices
• Input is any data the computer collects from the
outside world.
• That data comes from devices known as input
devices.
• Common input devices:
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Keyboard
Mouse
Scanner
Digital camera
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Computer Systems: Hardware
Output Devices
• Output is any data the computer sends to the outside
world.
• That data is displayed on devices known as output
devices.
• Common output devices:
– Monitors
– Printers
• Some devices such as disk drives perform input and
output and are called I/O devices (input/output).
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Computer Systems: Software
• Software, also called a program, tells the computer
what tasks to perform and how to perform them
• Installing is the process of setting up software to
work with the computer, printer, and other hardware
• There are two classifications of software:
– Operating Systems
– Application Software
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Software: Operating Systems
• An operating system (OS) is a set of programs containing
instructions that work together to coordinate all the
activities among computer hardware resources
Start and shut
down a
computer
Provide a user
interface
Manage
programs
Manage
memory
Coordinate
tasks
Configure
devices
Establish an
Internet
connection
Monitor
performance
Provide
utilities
Automatically
update
Control a
network
Administer
security
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Software: Operating Systems
• A stand-alone operating system is a complete operating
system that works on a desktop computer, notebook
computer, or mobile computing device.
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Unix
Linux
Mac OS
Windows (for example: Windows 7, Windows 8)
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Software: Operating Systems
Operating Systems Functions:
• Operating system controls various shut down options such as
sleep mode, hibernate.
• A user interface controls how you enter data and instructions
and how information is displayed on the screen
• It determines the order in which tasks are processed
• Plug and Play automatically configures new devices as you install
them
• A driver is a small program that tells the operating system how
to communicate with a specific device, such as printer driver.
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Software: Application Software
• Application software refers to programs that make the
computer useful to the user.
• Application software provides a more specialized type
of environment for the user to work in.
• Common application software:
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Spreadsheets
Word processors
Accounting software
Tax software
Games
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Windows 8
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Windows 8 Operating System
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Released by Microsoft in 2012
Designed to operate on touch-screen devices
Available for laptops, desktops, and tablet computers
Performing Tasks in Windows 8
• Use the mouse
• Touch the screen on touch-enabled devices
• Use keystroke commands
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Common Touch Gestures
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•
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Press and hold
Tap
Slide
Swipe
• Zoom
• Turn
• Swipe from edge
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Start Screen Components
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Windows 8 interface is the name of the Start screen
The screen contains tiles to hold apps
The screen is where you begin all activities
Most used applications are in one location on the screen
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Charms Bar
• Provides quick access to actions that are
frequently used
• Windows key + C to access by keystroke
• Move mouse to top- or bottom-right
corner of screen to access by mouse
• Contains five icons
• Replaces the Start button
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Windows 8 Search
• Using the Charms Bar
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Computer ethic issues
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Ethics
• Ethics are standards of moral conduct
– Standards of right and wrong behavior
– A gauge of personal integrity
– The basis of trust and cooperation in
relationships with others
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Computer Ethics
• Computer ethics are morally acceptable use
of computers.
– i.e. using computers appropriately.
• Standards or guidelines are important in this
industry, because technology changes are
outstripping the legal system’s ability to keep
up.
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Computer Ethics
• Four primary issues
– Privacy – responsibility to protect data about individuals
– Accuracy - responsibility of data collectors to authenticate
information and ensure its accuracy
– Property - who owns information and software and how can
they be sold and exchanged
– Access - responsibility of data collectors to control access
and determine what information a person has the right to
obtain about others and how the information can be used
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E-Mail Netiquette
• Promptly respond to messages.
• Delete messages after you read them if you don’t
need to save the information.
• Don’t send messages you wouldn’t want others to
read.
• Keep the message short and to the point.
• Don’t type in all capital letters.
• Be careful with sarcasm and humor in your
message.
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Computer Crime
• Computer criminals -using a computer to commit
an illegal act
• Who are computer criminals?
– Employees – disgruntled or dishonest --the
largest category
– Outside users - customers or suppliers
– “Hackers” and “crackers” - hackers do it “for fun”
but crackers have malicious intent
– Organized crime - tracking illegal enterprises,
forgery, counterfeiting
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Types of Computer Crime
• Damage to computers, programs or files
– Viruses - migrate through systems attached to files and
programs
– Worms - continuously self-replicate
• Theft
– Of hardware, software, data, computer time
– Software piracy - unauthorized copies of copyrighted
material
• View/Manipulation
– “Unauthorized entry” and “harmless message” still
illegal
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Computer Security
• Computer security involves protecting:
– information, hardware and software
– from unauthorized use and damage and
– from sabotage and natural disasters
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Measures to Protect Computer Security
• Restricting access both to the hardware locations (physical access)
and into the system itself (over the network) using firewalls
• Implementing a plan to prevent break-ins
• Changing passwords frequently
• Making backup copies
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Using anti-virus software
Encrypting data to frustrate interception
Anticipating disasters (disaster recovery plan)
Hiring trustworthy employees
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Computer Ethics
for Computer Professionals
• Competence– Professionals keep up with the latest
knowledge in their field and perform services only in
their area of competence.
• Responsibility– Professionals are loyal to their clients
or employees, and they won’t disclose confidential
information.
• Integrity– Professionals express their opinions based
on facts, and they are impartial in their judgments.
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