MaDeMoiSeLLe :)

4 TYPES OF DIRECT ACCESS STORAGE MEDIA

MAGNETIC DISKS

Description - use magnetic particles to store items such as data, instructions, and information on a disk's surface. Depending on how the magnetic particles are aligned, they represent either 0 bit or 1 bit. There are two types which are fixed head and movable head.
Examples- hard disks, floppy disks, removable cartridge.
Advantages- improves the media coercivity for a film structure, improve the thermal erasure problems related to a glass disk medium.
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OPTICAL DISCS

Description- a type of storage media that consists of a flat, round, portable disc made of metal, plastic and lacquer that is written and read by laser.
Examples - CD-ROM, CD-R, CD-RW, DVD-ROM.
Advantages- store items in a single track that spirals from the center of the disc to the edge of the disc. Can read and/or write on one side only. Mass storage capacity, low cost per bit of storage, long media life.
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FLASH MEMORY

Description - non-volatile computer memory that electrically erased and reprogrammed. For general storage and data transfer between computer and other digital products.
Examples- memory card, USB flash drives.
Advantages- non- volatile, fast read access time, better kinetic shock resistance than hard disks,
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MAGNETO-OPTICAL DISKS

Description- a kind of optical disc drive capable of writting adn rewritting data. Consists of a ferromagnetic material seal beneath a plastic coating.
Advantages - makes the media extremely reliable, able to report any problem to the operating system.
Examples - hard disk drives for some operating system.
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reference:

http://lists.freedesktop.org/archives/xdg/2004-August/002923.html http://en.wikipedia.org/wiki/Comparison_of_Windows_and_Linux

1. system that controls all the programs installed in a computer.It provides user-interface between users and the computer itself.
2. It provides support for loading and execution of other application programs.
3. It has system tools that monitor the computer performance, debug problems or maintain parts of the sytem.
4. An operating system is like a resource manager. It contorls how processes to access resources.
5. It protects applications from each other but yet share physical resources between them.
6. It provides virtual machine such as virtual processor and share CPU.
7. It also allocate and protect memory, enable virtual memory operations for application programs.
8. It manages files by using filling system and divide up storage space.
9. It organizes and control hardware and software so that it operates in predictable way.
10. It manages the networking within the computer.
11. It transforms the the physical world of devices, instructions, memory, and time into virtual world.
12. It ensure the applications continue to run when the hardware updates and upgrades occur.
13. It provides a consistent application interface, especially important if there is more than one of a particular type of computer using the operating system.
14. The operating system provides a virtual proccessor to provide the illusion that a computer is doing more than one thing at a time.
15. It provides device driver to that perform operations on behalf of programs for example input/output operations.
16. It introduces new functions as it abstracts the hardware. As an example, it introduces file abstraction so that programs do not have to deal with discs.
17. It can protects the system by controlling access to programs.
18. It responsible towards secondary-storage management such as free-space management, disc scheduling and storage allocation.
19. It keep tracks which part of memory are being used, allocate/deallocate memory space as required.
20. It deals with hardware specific driver for devices and keep it all hidden from the rest of the system.

20 CORE FUNCTIONS OF OPERATING SYSTEM

Cerita ini berkisarkan tentang seorang anak muda bernama Yuri Shibuya yang telah "ditelan" masuk ke dalam Kerajaan Syaitan, The Demon Kingdom. Rupa-rupanya, Yuri Shibuya merupakan utusan dari the great one untuk menjadi Raja Syaitan. Tanpa sebarang pengalaman menjadi seorang raja, Yuri dibantu pembantu-pembantunya untuk memerintah the demon kingdom. Banyak aksi-aksi yang menarik di dalam siri anime ini.Di samping itu, saya dapat menyaksikan sendiri kehebatan pereka anime dari Jepun. Jepun sangat terkenal dengan kebolehan pereka-pereka anime yang menhasilkan karya yang cukup mengagumkan. Saya masih menantikan karya dari pereka animasi tempatan untuk menhasilkan sebuah karya yang hebat dan boleh menarik minat semua lapisan masyarakat. Cerita animasi bukan hanya untuk tontonan kanak-kanak sahaja...
http://en.wikipedia.org/wiki/Kyo_Kara_Maoh!