Chapter 3: Storage Capacity

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Chapter 3Storage Capacity Storage Media

• Abbey Clark Susan Holl

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Whats in a Byte?!
A byte is a unit of storage created by on-off
pulses in a computer.
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Types of Storage

• Floppy Disk
• Mylar disk inside plastic shell
• Holds up to 1,444,000 bytes (1.44 megabytes)
• Getting a little dated some computers no longer
  include floppy disk drives
• Hard Disk
• Permanently mounted inside the computer
• Storage ranges but is typically multiple
  gigabytes (billions of bytes) or data
• Usually designated the C drive ? is the primary
  mass storage area for both programs and data

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• Removable Media
• Portable disks and cartridges that can be added
  to a computer
• Cartridges vary in size from 250 megabytes to 1
  gigabyte
• A portable hard disk is a self-contained disk
  and drive that plugs into a computer port
• Portable hard disks can vary from a few to
  hundreds of gigabytes in capacity
• Very convenient for transporting large
  multimedia files
• Examples USB flash drive, floppy disk, CD/DVD

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• CD-ROM
• Holes and flat areas are read by a laser mounted
  in a CD drive.
• CD-ROMs are read only, making them a one-way
  storage, unlike disks. (ROM Read Only Memory)
• CD-R
• CD-Rs are special CDs that can be written on once
  and read multiple times. They require a
  recordable drive to create them but can be read
  by any CD drive.
• CD-RW
• CD-RWs are CDs that are rewritable but require a
  CD-RW drive to store and erase data. CD-RWs can
  be read my most CD drives.
• CDs can store up to 650 megabytes
• Often used for multimedia because of their large
  capacity for storing audio, video, and text.

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• DVD-ROM
• DVDs are optical media that can store up to 17
  gigabytes of data.
• DVD-ROMs are read-only. After initial recording,
  data cannot be stored on them.
• DVD-Rs
• Are recordable but require a DVD writer
• Three competing formats are available DVD-R/W
  and DVD-RW. DVD RAM offers other features but is
  incompatible with some players.
• DVD-Rs and DVD-RWs can record up to 2 hours of
  quality video.

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Works Cited

• Lever-Duffy, McDonald Mizell. Teaching and
  Learning With Technology, Second Edition.
• www.courseweb.unt.edu/rhondac/fall2005/ch03.ppt29
  6,13,howcomputerswork