Introduction to Storage Devices
Storage Devices
Used to keep data when the power to the computer is turned off.
Medium/mediaLocation where data is stored.
Hard DiskUsually mounted
inside the computer’s system unit.
Can store billions of characters of data.Stated in forms of
bytes: Megabytes,
Gigabytes or Terabytes
Magnetic StorageRecording of data
onto disks or tape by magnetizing particles of an oxide based surface coating.
A fairly permanent type of storage that can be modified.
Used by mainframe or microcomputers
Floppy DiskRound piece of
flexible Mylar plastic covered with a thin layer of magnetic oxide and sealed inside a protective covering.
May be referred to as a “floppy”
3½ disk capacity is 1.44 MB or 1,440,000 bytes
Solid-State StorageFlash memory cards
Widely used in notebook computersUsed to record MP3 music files
Key chain hard drives Key chain flash memory
devicesConnects to a USB port
Optical StorageMeans of recording data as light and dark
spots on CD or DVD.Reading is done through a low-power laser
light.Pits
Dark spotsLands
Lighter, non-spotted surface areas
CD-ROM“CD – Read Only
Memory”Also called CD-R
CD-ReadStorage device that uses
laser technology to read data that is permanently stored on compact disks, cannot be used to write data to a disk.
CD-RW
“CD-Read Write”A storage device that reads data from CD’s and
also can write data to CD’s.Similar to a CD-ROM, but has the ability to write to
CD.
DVDDVD ROM
Digital Video Disk which is read only.DVD-R
Digital Video Disk which can be written to one time. It then becomes read only.
DVD-RWDigital Video Disk which can be rewritten to.
Blu-Ray Technology New standard in storageBlu-Ray
New disks use blue laser light instead of the red laser light used in traditional CD players
Disks may ultimately hold Over 30GB on one-sided disks Over 50GB on two-sided disks
Flash or Jump DrivesExternal storage devices that can be used
like a external hard drive.They have the capability to be saved to,
deleted from, and files can be renamed just like with a normal hard drive.
A hot swappable device is one which can be replaced whilst the server is still in operation.
You should only hot swap components when the component and operating system supports it.
The following components can be hot swapped: RAM, disk drive, power supply, NIC, graphics cards.
Hot swappable components are more expensive. Often only necessary when you need to keep a server operational 24/7.
Hot Swappable
List of Devices for Secondary Storage
Magnetic tape and disksCompact Disk Read-Only Memory (CD-ROM)Write Once Read Many - (WORM)Magneto-optical disksRedundant Array of Inexpensive Disks (RAID)Optical disksDigital Video DisksMemory cardsFlash memoryRemovable storage
ReferencesComputing Essentials 2005M. Guymon. Pleasant Grove High School