Signs of the Times

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Signs of the Times
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Wuzzle
Listen
Listen
Listen
Listen
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Storage media vs. devices

• Media is what you store the data on
• Diskette, tape, harddrive, CD-ROM
• Device is the equipment you have to use to
  actually store/retrieve the data
• Read-write head
• You need to understand how each speeds things up

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Storage media examples

• Diskette, Zip disk, tape, harddrive, CD-ROM, DVD,
  servers, RAID
• RAM, ROM, cache

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Storing vs. retrieving data

• Storing
• The process of transferring data to the storage
  medium
• Also called writing or saving files
• Retrieving
• The process of getting data from the storage
  medium
• Also called reading or opening files

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Storing on tape media

• Read/write head magnetizes the medium
• Magnetic particles now represent the ones and
  zeros
• Diskettes are an example

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Storing on optical media

• Laser burns, and reads the optical medium
• Pits and lands represent the ones and zeros
• CD-ROMs are an example

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Method of storage and access

• Tape reads/writes sequentially to the tape
• Called sequential access
• Must wind through the tape to find data
• Diskette, harddrive, CD-ROM, DVD use direct
  access
• Hash the key field then jump right to the
  location

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Speed of storage and access

• Also called the data transfer rate
• Rated in 1000s of Bytes per second

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Understanding storage

• The media affects speed
• The method of access affects speed
• The transfer rate of the storage device affects
  speed

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Speed is not everything

• Cost
• Flexibility
• Permanence
• Concurrent access
• Potential for data errors

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Harddrives

• Just a bunch of high capacity disks stacked up
• Like old time juke boxes with their stack of
  records
• A device called a controller takes care of the
  logic of storing data
• Ultra ATA, EIDE, SCSI are types of controllers

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Harddrive controllers

• EIDE are slowest, SCSI are a little better and
  Ultra ATA are the fastest
• But we go from harddrive, through the processor,
  to RAM
• DMA, or UDMA technology allows us to go right
  from the harddrive to RAM
• So pairing Ultra ATA with UDMA is the best

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Transfer speeds

• CD base is 150 Kbyte/second
• So a 48X CD is 48 times as fast
• DVD base is 11 Mbyes/second
• So a 5X is 5 times as fast
• Does it now make sense why DVDs provide much
  better picture quality?

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Expansion slots in the PC

• Used to add peripheral devices
• ISA type slots are old technology
• PCI type slots are current technology
• 32 or 64 bit data bus
• AGP will soon be standard
• Graphic card technology
• Make sure whatever you are putting into the slot
  matches technology-wise

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Expansion slots in laptops

• PCMCIA slots are designed for laptops
• Accept credit card size PC cards
• Usually only have the capability to accept two of
  these per laptop

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Expansion ports

• We got ports for the mouse, the keyboard, the
  printer, the monitor, the modem, the network
  connection, speakers and headphones
• Serial, parallel and USB ports
• Serial is slow, parallel is better, USB is the
  best

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Installing new devices

• Need a spare slot, or port
• Need the device (hardware)
• Need drivers
• Software that tells the PC how the device
  functions
• If it is a common device, your PC may already
  have the driver, if not you have to load the
  driver from a CD or diskette

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Monitors

• Resolution is how many pixels are used to make
  each screen
• 800 X 600 is standard, 1600 X 1200 is better
• 1600 X 1200 takes upgraded graphics card
• Number of colors supported provides more clarity
  on the screen
• 16 million colors is standard

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Monitors

• Rated by screen size, dot pitch, resolution and
  of colors supported
• Want large screen size (measured diagonally) 17
  is minimum, 21 better
• Want small dot pitch
• Measures how close the pixels are to each other,
  .23 or .26 millimeters is standard

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Monitors laptop vs. PC

• PC monitors are superior
• Laptop comes in two flavors
• active and passive
• Passive is fine, but you need to be right in
  front of the screen
• Active keeps its clarity even as you look at the
  screen at an angle.

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Printers

• Need to worry about resolution, speed, cost and
  ink usage
• Resolution
• 900 dots/inch is OK, 2400 needed for quality
  material
• Speed, measured in pages per minute
• Color takes longer
• Typical numbers are 10-15 ppm

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Printers

• Cost
• Laser and Ink Jet printers are inexpensive
• Up to a few hundred dollars
• Some are around 100
• Ink usage
• Size the printer for the job
• Printer refills run tens of dollars

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Wuzzle
GetYourAct
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Sample quiz questions

• What is the URL for this class?
• Where does the computer process data?
• The files that actually run things or make
  programs run have what extension?
• How do we identify internet host computers?

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Sample quiz questions

• What do we call the software that acts as the
  master controller for all activities that occur
  within a computer system?
• Word
• Application program
• Operating system
• .exe
• None of the above

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Sample quiz questions

• What do we call the address of a web page?
• A phone number
• A host address
• A URL
• Just B and C
• None of the above

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Sample quiz questions

• When you first start any browser, what is
  displayed?
• The MSN.com web page
• The Yahoo.com web page
• Your home page
• Your IP address
• None of the above

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Sample quiz questions

• To hide the people on a distribution list from
  the individual email recipients, which should you
  use?
• Yahoo! email
• Netscape email
• Bcc
• A distribution list
• Just a and b

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Sample quiz questions

• The boot process loads which of the following
  from the harddrive into memory?
• ROM
• RAM
• The operating system
• The application programs
• None of the above

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Sample quiz questions

• Which of the following is a typical value for RAM
  in a PC?
• 256 kbits
• 256 kbytes
• 256 Mbits
• 256 Mbytes
• 512 Gbits

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Sample quiz questions

• What is the binary equivalent of the decimal
  number 8?
• 8
• 08
• 1000
• 0008
• 0100

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Sample quiz questions

• The software that runs on your computer so you
  can view web pages is called a(n)?
• URL
• browser
• Internet
• ISP
• All of the above

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Sample quiz questions

• If a file has been incorrectly saved in the wrong
  folder, it is best to?
• Move it
• Copy it
• Delete it
• Rename it
• All of the above