Secondary Storage
Secondary storage (optical)
Table of contents Why was secondary storage needed? 1 Different types of optical discs: 1 1, CD (compact disc): 1 2, DVD (digital versatile storage) 2 3, Blu-Ray Disc (BD): 3 Which type of recordable disc should I choose: 3 Understanding the difference between the Live File System and Mastered disc formats: 3 Discs formatted with the Live File System option: 3 Discs formatted with the Mastered option: 4 Questions from students: 4 References: 5
Why was secondary storage needed?
There was a need for cheaper, more compact, more versatile storage devices with greater capacity. This lead to the invention of secondary storages, which offers the advantages of nonvolatility, greater capacity and greater economy. The selection of secondary storage devices requires the understanding of their characteristics: access method, capacity and portability. The most common forms of secondary storage include magnetic tapes, magnetic disks and optical discs. This essay deals with optical secondary storage devices.
Different types of optical discs:
1, CD (compact disc):
There are three types of CDs: CD-ROM, CD-R, CD-RW.
CD-ROM stands for compact disc-read only memory. After data has been recorded on a CD-ROM, it cannot be modified so it is mainly used by software suppliers. CD-recordable (CD-R) discs allow personal computer users to write data up to 650 or 700 MB on them. Moreover, they offer an inexpensive and convenient way of storage. CD is a piece of plastic. During manufacturing, it is impressed with little bumps, called pits, and then it is covered with an aluminium layer. The bumps make up a long spiral track of data, which would be five kilometres long, if it was lifted. The other parts of the aluminium layer are called lands. The CD player focuses the laser on the pits which reflect the light differently than the lands. While reading, a change from pit to land or land to pit indicates a one, while no changes indicate
Table of contents Why was secondary storage needed? 1 Different types of optical discs: 1 1, CD (compact disc): 1 2, DVD (digital versatile storage) 2 3, Blu-Ray Disc (BD): 3 Which type of recordable disc should I choose: 3 Understanding the difference between the Live File System and Mastered disc formats: 3 Discs formatted with the Live File System option: 3 Discs formatted with the Mastered option: 4 Questions from students: 4 References: 5
Why was secondary storage needed?
There was a need for cheaper, more compact, more versatile storage devices with greater capacity. This lead to the invention of secondary storages, which offers the advantages of nonvolatility, greater capacity and greater economy. The selection of secondary storage devices requires the understanding of their characteristics: access method, capacity and portability. The most common forms of secondary storage include magnetic tapes, magnetic disks and optical discs. This essay deals with optical secondary storage devices.
Different types of optical discs:
1, CD (compact disc):
There are three types of CDs: CD-ROM, CD-R, CD-RW.
CD-ROM stands for compact disc-read only memory. After data has been recorded on a CD-ROM, it cannot be modified so it is mainly used by software suppliers. CD-recordable (CD-R) discs allow personal computer users to write data up to 650 or 700 MB on them. Moreover, they offer an inexpensive and convenient way of storage. CD is a piece of plastic. During manufacturing, it is impressed with little bumps, called pits, and then it is covered with an aluminium layer. The bumps make up a long spiral track of data, which would be five kilometres long, if it was lifted. The other parts of the aluminium layer are called lands. The CD player focuses the laser on the pits which reflect the light differently than the lands. While reading, a change from pit to land or land to pit indicates a one, while no changes indicate
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