how is data organised on a magnetic disk?

The basic principle of saving data in a magnetic disk is by the aligning of the fe magnetic particles present on the surface.

Inorder to reference each location of the disk, there has to be an Address (kind of) for it. This is done by dividing the disk into Cylinder, Head, Sector.

C

ylinder:- Think of the disk to be the same way as a box of CDs on a spindle. Now think of using a compass to draw concentric circles on the top most circle. now if you imagine each cirle across all the disks, ie. each circle to go down till the last, then you see you have a pipe, which is the cylinder.

Head: Imagine you want to write on the CDs while they are in the spindle...You would require a pen which can go to each disk in the stack and write on the top and bottom part.. This is the same as HEAD concept.

Sector: Now draw radials on the first disk, cutting the circles you had drawn.The space between two radials is called a sector. (V -shaped area)

Block: They refer to the BOXES that are created when the concentric circles are cut by two radials.

In a harddisk, a block will be the least level of physical addressing. A block can have a specific amount of data (512,1024 etc). This means that you can store data in multiples of the block size only.

computer can use magnetic disk to store data

the disk surface must be magnetically mapped so that the computer can go directly to a specific point.

it without through searching data.the process of mapping a disk is called intializing

THe hda is divided up into tracks and each track has sectors. The computer organizes all the information on theses different sectors. The first sector is the MBR.. Master boot record.. this is the most inmportant and then the rest are for your programs and data.

All the explanation here is difficult. Just go to this site.

http://en.wikipedia.org/wiki/Hard_disk

The below link should answer your question. Hope this helps and good luck!