Computers Simplified

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Transcript Computers Simplified

Computers Simplified
Supplemental Lecture
Notes
Introduction
Chapter 1
Parts of A Computer
 Hardware – you can see it or touch it
 Software – set of electronic instructions
– Application software – specific tasks
– Operation software – controls overall activity
 Peripherals – anything attached
What Computers Do
 A computer collects (input), processes,
stores and outputs information.
Storage Simplified
 Bit: on or off
– Smallest unit of information in a computer
 Byte: one character
– 8 binary digits
Bigger Is Better
 Kilobyte (KB)
– 1,024 character
• One double-spaced typed page
 Megabyte (MB)
– 1,048,576 characters
• A book
 Gigabyte (GB)
– 1,073,741,824
• A shelf of books
 Terabyte (TB)
– 1,099,511,511,627,776 characters
• A library of books
Set-top Box
 Computer device that you connect to your
television.
– Use telephone or cable connection
– Email of Internet
Typical System
 Computer case
 Monitor
 Printer
 Speakers
 Modem
 Keyboard
 Mouse
Computer Components
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Power supply
Hard drive
Expansion card
Expansion slot
System board
CD-ROM or DVD-ROM
Floppy disk
Drive bay
Central Processing Unit (CPU)
Random access memory (RAM)
Power Plays
 The capacity of a power supply is
measured in watts
 Computer uses 250; light bulb uses 60
 Can use
– Surge protector
– UPS
Ports
 Ports are connectors at the back of a
computer system that you use to plug in an
external device. This allow instructions and
data to flow between the computer and the
device
Any Port in a Storm
 Parallel port – 25 holes; female connector; LPT1; printer
or storage devices
 Monitor port
 Keyboard port
 Serial port – 9 or 25 pins; male connector; COM1; mouse
or modem
 Game port
 Network port
 USB port
– 127 devices
– Printer, modem, joy stick
Growing
 An expansion card is a circuit board that
lets you add new features to a computer
– Video
– Modem
– Sound
– Network Interface
Upgrades
 Upgrading refers to replacing an old or obsolete
component with a newer component to improve
the efficiency of the computer
 Upgrading also can include adding a new
component like a tape drive or DVD to increase
the capabilities of a computer
 Increasing the amount of memory in a computer
is one of the most effective upgrades you can
perform
Input and Output
Chapter 2
Mouse Actions
 Click – selects
 Right click – displays commands
 Double click – opens
 Drop and Drag – moves items on screen
Mice
 Types
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Conventional
Wheel mouse
Wireless mouse
Programmable mouse – e.g. three buttons
Optical sensor mouse
 Other devices
– Touchpad
– Trackball
– Pointing stick
Keyboards
 There are 101 keys on a keyboard to help you
input information
 Function keys let you perform specific task
 Can use CNTL-x shortcuts to execute
commands
– CNTL-C – copy
– CNTL-X – cut
– CNTL-V – paste
 Windows key will quickly display the start
menu
Printers
 Speed of a printer is measured in pages per
minute (PPM). A higher speed represents faster
output
 Resolution determines the quality of images
– A higher resolution results in sharper images
– Printer resolution is measured in dots per inch (dpi)
• 600 dpi is acceptable; 1200 is better for images
– Resolution expressed with two numbers represents
dots per inch across and down
Types of Printers
 Ink-jet: has a print head that sprays ink
through tiny nozzles onto a page
– 2 to 10 pages (ppm)
– 360 to 2400 dots per inch
– Color printers spray cyan, magenta, yellow
and black to create different colors
 Laser-printer
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Works like a photo copier
Speed of 4 to 16 pages
Have a CPU
600 to 2400
Memory – 2mb to 8 Mb
Other Types
 Dot matrix
– Print head contains small blunt pins that strike
an inked ribbon
• Useful for multi-part forms
 LED printer
• Similar to lasers but cheaper
 Color photo printer
 Multifunction Printer
Print Buffer and Spoolers
 Printer buffer: section of memory printer
stores information waiting to print
 Printer spooler: program on your computer
that stores information waiting to print
– Stores more information than the buffer
– One spooler for each connected printer
Monitors
 Video cards translate instructions from
the computer into a form Most
computes the monitor can understand
– require at least 2 mb of video card
memory
– Accelerated Graphics Port (AGP) – uses
AGP bus to communicate directly with
main memory
– 3D Graphics Accelerator has chip called a
GPU optimized for 3-D graphics
Monitor Metrics
 The smaller the dot pitch, the crisper the
image
– 0.28mm is acceptable
 Refresh rate is measured in hertz (Hz)
– Times per second computer redraws the image
– 72 Hz or more is acceptable
Resolution
 Amount of information a monitor can display
– Measured by the number of horizontal and vertical
pixels
 Monitors switch settings based on the resolution
and refresh rate of video card
 Video card determines number of colors a
monitor can display
– 256 suitable for most home use
– 24-bit displays more colors than eye can distinguish
Communications
 Modems let a computer exchange
information through telephone lines
 Speed of a modem determines how fast it
sends and receives messages
– 56,000 bps (56 Kbps)
• V.90 standard: receive 56K and send 33.6K
– Speed at which information flows depend on
the quality of the phone line
 A modem needs a communications
package to manage the transmission of
information
 Data compression – squeezes together data
High-speed Connections
 ISDN – Integrated Services Digital Network
– Digital phone line
– 56 Kbps to 128 Kbps
 Cable Modem
– Same cable as TV
– 4000 Kbps
 DSL – Digital subscriber line
– High speed digital phone line
– 1000 – 6000 Kbps
 Satellite
Sound Cards
 Sampling Rate: at least 44.1 KHz
 Full-duplex
– Talk and listen at same time
 Musical Instrument Digital Interface (MIDI)
support
– Wavetable synthesis
• Actual recordings
– FM synthesis
• Imitated sounds
TV Tuner Cards
 Require a video card to operate
Scanners
 A scanner is a device that reads
images and text into a computer
– Most scanners come with Optical
Character Recognition (OCR) software.
This software places scanned text into a
document that can be edited in a word
processor
– Color dept is measured in bits and
indicates the number of colors a scanner
can detect
• 36 bit color depth is acceptable
Resolution
 Resolution determines the amount of detail
a scanner can detect
• Ranges from 600 dpi to 2400 dpi
• You usually don’t need to scan at a higher
resolution than a printer can produce or a monitor
can display
– Most monitors are 73 dpi
– Printers vary
Cameras
 Resolution is measured in megapixels
– 1000 x 1000 pixels
– 1, 2 and 3 megapixel cameras are available
 Digital video cameras use a Charged Coupling Device
(CCD) to capture video
– Quality depend on amount of detail a CCD can detect
• Most CCD’s have resolution between 250,000 and 700,000 pixels
 Web cameras – resolution and speed determine quality of
image
– Common transfer rates
– 15 frames per second at 640 x 480 pixels
– 30 frames per second at 352 x 288 (clearer but smaller)
MP3
 Sound format used to CD-quality music
over the Internet
– Compresses sound
 Commonly 64 bit memory
USB and Firewire
 High-speed ports that allow information to
quickly transfer between a computer and an
external device
– USB
• Supports up to 127 device
– USB 1.0: 12 megabits per second
– USB 2.0: 480 Mbps
– FIREWIRE
• 63 devices at 400 Mbps
• Can purchase Firewire expansion card
Processing
Chapter 3
CPU
 Central Processing Unit
 Processes instructions, performs calculations,
and manages the flow of information through a
computer system
 Performance:
– Each generation of CPU is more powerful than the
one before
– CPU speed is a major factor in determining how fast a
computer operates (faster the speed, faster computer
operates)
• Measured in megahertz (MHz)
Processing
 The Central Processing Unit (CPU) is the
main chip in a computer
– Processes instructions
– Performs calculations
– Manages the flow of information
Types of CPUs
 Intel Pentium Processor
– Speeds of 450 MHz to 1.13 GHz
 Intel Celeron
– Needs of home machines (500-700MHz)
 AMD Athlon Processor
– Business and home use
 AMD Duron Processor
– Home use
 VIA Cyrix Processor
– Inexpensive CPU
Processing
 Random Access Memory – Temporarily stores data
inside a computer
– Constantly overwritten
– Measured in megabytes (MB)
• 64 minimum these days100 MHz (millions of cycles per
second)
– Dynamic RAM is type of memory chip that makes up
memory in many computer systems. Access speed measured
in megabits
• Most system boards can support access speed of Single Inline
Memory Module (SIMM) – 9 memory chips
• Dual Inline Module (DIMM) – 18 memory chips
 If you have limited memory or you have many
programs open, your computer may need to use part of
the hard drive to simulate more memory
Using Memory Cache
1. Look through documents on your desk
(internal cache)
2. Look through documents in your desk
drawer (external cache)
3. Looking through documents in your
filing cabinet (RAM)
Using Memory Cache
1. Look through documents on your desk
(internal cache)
2. Look through documents in your desk
drawer (external cache)
3. Looking through documents in your
filing cabinet (RAM)
Storage Devices
Chapter 4
Memory Cache
 Speeds up computer by storing data the computer
has recently used
– Internal Cache: On CPU chip (L1 or primary cache
– External Cache: On the system board and consists of
Static RAM (SRAM chips)
• Sometimes built into chip
 RAM – slower main memory
– Each time the computer requests data from RAM, the
computer places a copy of the data in memory cache
• Constantly contains the most recently used data
BUS
 Electronic pathway that carries information
between devices in a computer
– Bus Width (think lanes of a highway)
• 8 bits is one character
– Bus Speed (think speed limit)
• Measured in MHz (millions of cycles per second)
Bus Types
 ISA (Industry Standard Architecture)
– Slowest and oldest
– 16 bits; 8MHz (millions of cycles per second)
– Pentium, Pentium II
 PCI (Peripheral Component Interconnect)
– 32 or 64 bits
– 66 MHz
– Support Plug and Play
– Pentium II, III, 4
 AGP (Accelerated Graphics Port)
– Between video card and main memory
– 32 bits; 66 MHz
Using a Hard Drive Correctly
 Virus protection
 Backups
 Defragmentation
– Prevents files from being broken up for storage
 Repairing a Disk
 Disk Cleanup
 Data compression
– Only if disk is running out of space
Hard Drives
 Magnetically stores data on rotating disks
called platters
 Stores your operating system and programs
 Document will not be lost when you turn
off the computer
 Capacity is measured in bytes
 Speed is measured in revolutions per
minute
File Systems
 File system determines how information is
stored on a hard drive
– FAT
– FAT32
– NTFS
Connection Types
 EIDE (Enhanced Integrated Drive Electronics) –
Called IDE
– Supports total of 4 devices (any drives)
– Ultra Direct Memory Access (UDMA) is enhanced
IDE
 SCSI (Small Computer System Interface)
– Called ‘scuzzy”
– Supports 7 devices
– Expensive
Relation of Cache & Hard
Drives
 Disk cache speeds up the computer by
storing the data the computer has most
recently used
– Constantly updated
– Area of memory
– Fast access
– Then hard drive is searched
Floppy Drives and Drives
 Removable media
– Can be write-protected
– Can be damaged magnetically
CD-ROM
 ROM (Read-only memory) - can’t be changed
 650 Mb of data
– Equal to entire set of encyclopedias
– 400 Floppy disks
– Music, games, software installs
 Speed determines how fast a disk spins
– Look for 24X
 Speed of CD-ROM drive is the transfer rate
– In Kb (e.g. 3600Kbs)
CD-R & CD-RW Drives
 CD-R (Compact Disc – Recordable)
– Permanent store; not erasable
 CD-RW
– Can be erased and rewritten
– Read / Write and Re-write speeds
– Usually 74 minutes
 Special software needed to record onto a disk
– Referred to as burning a CD
DVD-ROM Drive
 DVD – Digital Versatile Disk
– Generally cannot change the information stored on a
disk
– Similar to CD but stores more information
– Speed determines transfer rate (6 X)
– Capacity
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1 side / 1 layer – 4.7 GB
1 side / 2 layer – 8.5 GB
2 sides / 1 layer – 9.4 GB
2 sides / 2 layers – 17 GB
Tape Drive
 Backup helps you copy files to tape cartridges
 Tape drives come with backup programs
 Schedule backups to run at night
– Backup programs compress data together
 Try to find a drive that can store the entire
contents of your hard drive
 Travan drives are the most common type of tape
drives – 10 GB
 DAT drives are faster than a Travan – 24GB
Tape Backups
 Full
 Incremental
Removable Storage Devices
 Jazz Drive – 2 GB
 Zip Drive – 250 MB
 LS-120 Drive – 120 MB
Software
Chapter 5
Software
 Software helps you accomplish specific tasks
 Manufacturers also may create minor software updates called
patches, to make corrections or improvements to software
 Application software:
– Word processor helps you create professional looking documents
quickly and efficiently
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Documents
Editing
Printing
Formatting
Tables
Images
Mail merge
Spreadsheets
 Perhaps the original ‘killer app’
– Manage finances on your computer
– Manage data in a list
 Funtions
– Formatting
– Editing
– Formatting
– Formulas and calculations
– Charts
Database Programs
 Helps you manage large collections of
information
– Phone directories
– Product listings
– Payroll information
 Features
– Store information
– Find information
– Analyze and print information
Databases
 Organized in:
– Tables
• Collection of information about a specific topic
– Field
• Category of information
– Record
• Single instance of information
Application Suites
 Word processing
 Spreadsheet program
 Presentation program
 Information management program
– Mail, calendars, address book
 Database program
Utility Programs
 Utility: A program that performs a specific task
on your computer
– Norton utilities: recover files
– Virusscan: anti-virus
– Acrobat Reader: View PDF (Portable Document
Format) files
– Winfax pro
– ViaVoice – Speech recognition
– WinZip – Compress and decompress files
Operating Systems
Chapter 6
Operating Systems
 Software that controls the overall activity of the
computer
– Ensure that all of the parts of the computer work
together smoothly
– Functions:
• Control hardware
• Run software
• Manage information
– Programs that run on one operating system platform
do not generally run on others
Types of Operating Systems
 MS-DOS
• Command driven
 Windows
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Windows 3.1
Windows 9X (95, 98)
Windows ME
Windows XP
Windows NT
Windows 2000
• GUI – “Graphical User Interface”
 UNIX
 MAC OS
MS-DOS
 Characterized by the C:\> prompt
 Cursor is the flashing line on the screen
where you type
 File Organization: Root directory is C:\
– Path describes the location of a file
 Files: Name is 8; extension is 3
Windows 3.1
 Not technically an operating system
– Works with MS-DOS
 Program Manager is the control center
 File Manager used to organize files
 Desktop – Background area
Windows 95
 True operating system – eliminated
reliance on DOS
 My Computer lets you browse all folders
and documents
 START button allows you to quickly
access programs and documents
 Windows Explorer: Shows the location of
each folder and document on the computer
Windows -98
 Similar to Windows-95
 More reliable than Windows-95
 Has multiple monitor capability
 Uses FAT32 file system
 Includes Internet functionality
• Explorer
• Outlook Express
• Front Page Express
Windows ME
 Millennium Edition
 Similar to 98
 Added features
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Record videos using Windows Movie Maker
Manage Multimedia Files with Media Player
Restore your computer
Set up a home network
Phone home
Windows XP
 Windows XP, which is available in Home and
Professional editions, was released in October. Windows
XP Professional is intended to replace Windows 2000
Professional. Windows XP Home Edition was designed
as the upgrade for the Windows 95, 98 and Me line.
 Although the two systems run on the same kernel, or
engine that drives the operating system,Windows XP has
many features that are not included in Windows 2000.
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System Restore
Built-in Firewall
Much more graphic
NT look and feel
Multiple users
CD-RW functionality
Windows NT
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Features advanced networking and security
Separates Workstations and Servers
Runs Windows-9X programs
Workstations communicating with NT can run:
– NT
– Linux
– Win 9X
– Mac OS 9
Windows 2000
 Supports larger network
 Server and client re-united
UNIX
 Can run single computer or entire network
 Developed on mainframes in late ’60’s
 Versions:
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SCO
Solaris
Linux
HP-UX
AIX
 Most widely used operating system on Internet
Unix Features
 Harder to install but provides more power
and control
 True multi-tasking OS
 Security
LINUX
 Unix-based system offered as freeware on the
Internet
– Can purchase from Red Hat, Corel or mandrake
 Can be set up with GUI operating system called
GNOME or as a command line system
 Features:
– Software analogous to Windows available
– Accounts for root and personal functions are available
MAC OS
 Version 9
– Advanced sound, video and graphics
– Internet (Sherlock2)
 Version 10
– New GUI
• Includes dock for frequently accessed items
– Graphics: PDF, QuickTime and OpenGL
– Improved operating system Kernel
Portable Computers
Chapter 7
Notebook Computes
 Small lightweight computer you can easily
transport
– Built-in keyboard and pointing devices
 Batteries
– Nickel-metal hydride (NiMH)
– Lithium Ion
• More expensive but lighter and stronger
– Last only a few hours
Laptop Features
 Screens
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Uses liquid crystal display (LCD)
Measured diagonally
Backlit
Can use a full-size monitor
Types
• Passive Matrix
– Hard to view from an angle
• Dual-Scan
• Active Matrix (also called a Thin Film Transistor)
– Can be view from oblique angles
Laptop Features
 Input / Output Devices
– There are several device that let you move the pointer
around the screen of a notebook computer
• Pointing stick
• Trackball
• Touchpad
– Keyboards
– Modem
– Sound card and speakers
Laptop Features
 Input / Output Devices
– There are several device that let you move the pointer
around the screen of a notebook computer
• Pointing stick
• Trackball
• Touchpad
– Keyboards
– Modem
– Sound card and speakers
Laptop Features
 Storage Devices
– Hard Drive
– CD-ROM or DVD-ROM
– Floppy Drives
– External Drives
– PC cards: Personal Computer Memory Card
international Association (PCMCIA)
• Compact Flash Memory
Processing
 The Central Processing Unit (CPU) is the
main chip in a computer
– Processes instructions
– Performs calculations
– Manages the flow of information
PC Cards
 A PC Card adds a new capability such as
memory, different devices or connectivity
to a laptop
– Type I, II, III
– Can have one Type III card or two Type I or
IIs
Other Features
 Network Interface Card
 Infrared port
 Port Replicator
– Lets you connect many devices to a notebook
at once
 Docking station adds a keyboard and a
full-size monitor to the port replicator
Introduction to Handhelds
 Portable computer small enough to carry
– Called a Personal Digital Assistant (PDA)
– Popular Handhelds
• Palm
• Visor
• CI
– Features
• Stylus
• Collapsible keyboards
• Wireless modems
Handheld Systems
 Operating Systems
– Palm OS
– Windows CE
 Electronic organizers
 Information exchanges
 Other technologies
– Smart phones
– RIM BlackBerry – two-way paging
Macintosh Computers
Chapter 8
Macintosh Examined
 First computers with mouse and GUI
 Advantages
– Ease of use
– WYSIWYG (what you see is what you get)
 Types
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Power Mac (G4)
Cube – Quarter-size
iMac – all-in-one
PowerBook
 OS
– Versions 9 & 10
Ports
 Connectors for external devices
– FireWire
• 63 devices
• High speed for multimedia like cameras and external drives
– USB Port
• 127 devices
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Network Port
Speaker Port
Microphone Port
Monitor Port
I/O Devices
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Mouse
Keyboard
Monitor
Video
Sound
Printer
Modem
Imaging
Processing
 All new Macintosh computers use PowerPC
microprocessors called Reduced Instruction Set
Computer Chips (RISC)
 Types of CPUs:
– G3
– G4 – may be in tandem
 BUS: Peripheral Component Interconnect(PCI)
bus with width of 32 or 64 bits and speed up to
64 MHz
 128 mb of RAM is recommended
Networks
Chapter 9
What Is a Network
 A network is a group of connected
computers that allow people to share
information and equipment
Types of Networks
 LAN (Local Area Network) connects
computers within a small geographic area
like a building
 WAN (Wide Area Network) connects
computers across a large geographic area
like a city or country (often via satellite)
 Internet: World-wide network of networks
Advantages
 Road warriors
 Eliminate “sneakernet”
 Share information
 Share equipment
Who Runs It?
 A network administrator manages the
network and makes sure it runs smoothly
– Often called a systems administrator or an IS
manager
Network Applications
 Electronic mail
 Groupware
– Calendaring
– Scheduling
 Video-conferencing
– Requires sound card, speakers, mike & camera
Physical Networking
 Hubs
– A hub is a device that provides a central location
where all the cables on a network come together
 NICs (Network Interface Card)
– An expansion card that physically connects each
computer to the network
 Cables
– Coaxial, Unshielded Twisted Pair (UTP), Shielded
Twisted Pair, Fiber-optic
– Wireless
How Information Is Stored
 Client-Server:
– Used for large networks
– Files are stored on a central computer and everyone
who can access the network can be given access them
• Easy to create scheme to backup and protect files
– Client: a computer that can access information stored
on the server
– Server: Central computer that stores files
– NetWare, UNIX, Windows NT/2000
How Information Is Stored
 Peer-to-Peer:
– Used for a small number of computes (e.g. 10)
– Files stored on own computers; access given
to them to others on the network
– LANtastic, Windows-98, Windows-ME
How Information Is Exchanged
 Ethernet:
– Most popular and least expensive solution
– Each computer waits for a pause before
sending information
• Like polite conversation
– Collisions between information often occur
• Computers wait a moment, then resend
– Ethernet – 10 Mbps, Fast Ethernet – 100
Mbps, Gigabit Ethernet 1000 Mbps
How Information Is Exchanged
 Token-ring is a type of network where a token
that collects and delivers information is passed
from compute to computer
– Speeds of 4 or 16 Mbps
 Asynchronous Transfer Mode (ATM) is a type of
network that works by sending information in
equal-sized pieces called cells
– 25, 155, 622 or 2488 Mbps
– Often networks networks
Network Security
 Firewall – specialized hardware or
software package designed to protect a
private computer network from
unauthorized access
– Think “Moat”
 User name and password
– Used for authentication
– Good passwords
Intranet
 Small version of the Internet in a company
 Uses familiar web-browsers and email
packages
 Allows hyper-linking
 VPNs (Virtual Private Network)
– End-to-end encryption
– More cost efficient than private lines
Internet and WWW
Chapter 10
Internet Fundamentals
 Dates from DARPA in the 1960s
 Consists of thousands of connected networks
around the world
– Each organization on the Internet is responsible for
maintaining its own equipment
• These organizations allow you to pass-through their nets
 Designed to provide multiple routing to bypass
disabled computers
 Called cyber-space or the information
superhighway
Internet Offerings
 Electronic mail (Most popular application)
 Information
 Entertainment
 Discussion Groups
 Chat
 Programs (Shareware)
 Online shopping
Connecting
 Computer
 Software
 Modem or high-speed connection
 ISP (Internet Service Provider)
– Access for a fee
World Wide Web
 Part of the Internet consisting of a huge
collection of documents stored on computers
around the world
– Web server: computer that stores and delivers web
pages
– Web site: collection of web pages
• URL (Uniform Resource Locator) – unique address
– HTTP, Computer, Directory, Name of Page
– Hyperlinks jump to different web pages
Browsers
 A program that lets you view and navigate
information on the World Wide Web
– Home Page: Web page that appears each time you start
your web browser
– Browser:
• Internet Explorer
• Netscape Navigator
– Features
• Bookmark
• History lists
Multimedia
 MP3 – compressed files containing music or
video
– WinAmp
 Streaming video – requires player
– RealPlayer, QuickTime
 Enhancements
– Java
– JavaScript
– ActiveX
Web Portal
 Central starting point for browsing
personalized by the individual
– Yahoo, Excite, Go, Lycos
– Info
– Free services like email, shopping, chat,
games, stock quotes and sports scores
Shopping
 Auctions
 Secure web sites – i.e. HTTPS
Children on the Web
 Inappropriate information
– Pictures
– Documents
 Protection
– Adult supervision
– Browser restrictions
– Restriction programs
• CyberPatrol
• NetNanny
Create & Publish Web Pages
 HyperText Mark-up Language is a
computer code used to create Web pages
 There are many programs available, called
visual editors which can help you create
Web pages without having to learn HTML
 Publishing your pages – loaded to an
addressable server
Electronic Mail &
Mailing Lists
Chapter 11
E-Mail
 E-mail is a fast, economical and
convenient way to send messages to
family, friends and colleagues
 Addresses
– Location of an individual mailbox on the
Internet
– User name, @ sign, domain – no spaces
Web-based E-mail
 Don’t need email client
 Popular Web-based E-mail Services
– www.hotmail.com
– www.email.com
– mail.yahoo.com
Organization
 By type:
•
•
•
•
•
•
 By country
.com
.edu
.gov
.mil
.net
.org
Other new codes have been defined
•
•
•
•
•
•
Australia - .au
Canada - .ca
Ireland - .ie
Italy - .it
Japan - .jp
United Kingdom - .uk
E-mail Features
 Address books
 Signatures
 Attachment of files
– Try to keep under 50Kb
– Sometimes certain types of files are
screened
E-Mail Issues
 Emoticons
 :-)
 Abbreviations
– LOL
– TTFN
 Netiquette
– Shouting
– Flame
Viruses
 An e-mail virus is a program that can
disrupt the normal operation of a computer
– Display of unusual messages
– Destroying files on the hard drive
– Sending mail to people in your address book
 Opening files; sometimes only in preview
 Virus programs available commercially
– Must be kept up-to-date
Newsgroups and Chat
Chapter 12
Mail Groups
 A mailing list is a discussion group that
uses e-mail to communicate
– A list of mailing lists is at www.liszt.com
 Moderated vs. un-moderated lists
 Must subscribe to participate
 Two addresses
– Mailing list addresses
– Administrative addresses
Newsgroups
 A discussion group that allows people with
common interests to communicate with each
other
 USENET (User’s Network)
– All the computes that distribute newsgroup
information
 Messages
– Individual posts
 Threads
– Messages and all replies
Addressing
 First word describes the main topic
 Each additional word is separated by a dot
and serves to narrow the topic
Networking Aspects
 Newsreader – program that lets you read
and post online
– Microsoft Outlook has a built-in reader
– Gravity
– Free Agent
 News server
– A computer that stores newsgroup messages
Newsgroup Categories
alt
biz
comp
misc
rec
sci
Soc
talk







General Interest
Business
Computers
Miscellaneous
Recreation & Hobbies
Science
Social
(culture/politics)
 Debate
•
•
•
•
•
•
•
alt.fans.actors
biz.entrepreneurs
comp.security.misc
misc.books.technical
rec.food.recipes
sci.physics
soc.history
• talk.politics.misc
Newsgroup Etiquette
 Lurk first
 Read FAQ
 Reply
 Send a private reply
Chatting
 One of the most popular features on the Internet
(but no one admits to doing it)
 Text-based
 Multi-media
– Internet Relay Chat (IRC) channels
• Need a program to participate (www.mirc.com)
 Instant messaging allows you to communicate
privately with others
– MSN or AOL