Introduction to Storage Devices

Storage Devices Used to keep data when the power to the computer is turned off. Medium/media Location where data is stored.

Hard Disk Usually mounted inside the computer’s system unit. Can store billions of characters of data. Stated in forms of bytes: Megabytes, Gigabytes or Terabytes

Magnetic Storage Recording 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 Disk Round 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 Storage Flash memory cards Key chain hard drives Widely used in notebook computers Used to record MP3 music files Key chain hard drives Key chain flash memory devices Connects to a USB port

Optical Storage Means of recording data as light and dark spots on CD or DVD. Reading is done through a low-power laser light. Pits Dark spots Lands Lighter, non-spotted surface areas

CD-ROM “CD – Read Only Memory” Also called CD-R Storage 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.

DVD DVD ROM DVD-R DVD-RW Digital Video Disk which is read only. Digital Video Disk which can be written to one time. It then becomes read only. DVD-RW Digital Video Disk which can be rewritten to.

Blu-Ray Technology New standard in storage Blu-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 Drives External 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.

Hot Swappable 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.

List of Devices for Secondary Storage Magnetic tape and disks Compact Disk Read-Only Memory (CD-ROM) Write Once Read Many - (WORM) Magneto-optical disks Redundant Array of Inexpensive Disks (RAID) Optical disks Digital Video Disks Memory cards Flash memory Removable storage

References Computing Essentials 2005 M. Guymon. Pleasant Grove High School