Short Note on Hard Disk and Optical Disk and Floppy Disk

Short Note about Hard Disk and Optical Disk and Floppy Disk Points : Short Note about Hard Disk, Optical Disk and Floppy Disk Hard Disk Hard disk usually has more capacity than diskettes and offers faster access to the data they hold. These are also called platters ma metal box for heavily storage. In the beginning hard disk had the capacity of 10MB these days the maximum storage capacity is 80 or more. Optical Disk A laser hits a layer of’ metallic material surface of disc. When data is being entered hot laser produces tiny spots on the disc surface to read data the laser scans the disc and a lens pick up different light reflections from various spots. Normally WORM (write ones Read many) or CD-Rom (compact disc read only memory) is used for optical storage Floppy Disk Floppy disk is easy portable disk within its jacket there is a circular plastic thin disc. Which is magnetically coated this plastic magnetically created disc. Its contains tracks on it and each track is divided into several sectors. The floppy disc when inserted into the disk drive rotates at 360 rpm and a read write head reciprocates on it to store/retrieve information. These disk come in various size and mathematically the capacity of the disk is calculated as
1 track = 18 sectors
80 tracks = I 8x80 = 1440 sectors
double sided, 80 tracks = 1440 x 2 = 2880 sectors .
but. 1 sector 512 bytes
double sided, 80 tracks = 2880 x 12 = 1474560 bytes
but 1024 bytes = 1 kb