Chapter 3 item 4

Discuss the various types of optical disc systems available and how they differ from each other and from magnetic systems?

Optical discs as in CD's and DVD's can store data optically by using laser beams instead of magnetically
they are 41/2 inche circles they can come in smaller sizes.

They are divided in to secctors just like magnetic disks bur use a single grooved track. can be use for read only, recordable or rewritable have a high memory of 650MB

These disks can bur burned the spots on the disksare used to represent the data's 1 & 0, the areas that dont change are called lands.

The read only disks CD-ROM can only be read from, can hole up to 650 data the DVD-ROm can hold4.7GB single sided and 8.5GB double sided.

CD-R, DVD-R,DVD+R can all be written on but the data cannot be erased from the disk, CD-R are mainly used for backup or sending larger files. the DVD-R is used in the same way when there is more storage needed, eg home movies.

Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-ShareAlike 3.0 License