SEB070017 - OS(Device management)

Operating System
Tutorial 5
Ng Chi Beng
SEB070017

Device Management

1.Magnetic disk












Description
- the storage of data on a magnetized medium
- use non-volatile memory pattern to store data
- The information is accessed using one or more read/write heads


Advantages
-high storage capacity
-reliable
-gives direct access to data
-there are removable and cartridge types


Example
-Hardisk
-zip disk
-floppy disk

2.Optical disc


Description
- using a low-powered laser beam
- stored data as micron-wide dots of light and dark

Advantages
- The greater control and focus possible with laser beams means that more data
can be written into a smaller space.
- inexpensive to manufacture and data stored on them is relatively impervious
to most environmental threats
- faster than magnetic disc
- large storage capacity
- speed faster than magnetic discAdvantages


Examples
-Blue-ray
-CD-ROM
-CD-RW
-CD-R
-DVD

3.Flash memory


Description
- technology that primarily used in memory cards and USB flash drives for
general storage and transferring data
- non-volatile, which means that no power is needed to maintain the information
stored in the chip


Advantages
- low cost
- convenience to use and easy to bring.
- Small size
- large storage capacity 8 MB to 1 GB
- include password protection
- ability to run software right off the USB drive

Examples
- memory card
- flash drive
- flash pen
- thumb drive
- key drive
- mini-USB drive.
- Removable hardrive
- Smart card

4.Magneto-optical disc


Description
- do not require a special file system for example they can be formatted as
FAT, HPFS, NTFS
- consists of a ferromagnetic material sealed beneath a plastic coating


Advantages
- can store several GB of data.
- faster than magnetic and optical
- slower than hardisk
- back up files on a personal computer.

Examples
-quadrilayers Magneto-optical disk