In 1970, IBM introduced a new medium for storing data.
This medium consists of a circular piece of thin plastic material, approximately eight inch in diameter coated with an oxide material.
This circular piece of plastic material or disk was enclosed in a square protective jacket with small cut at the top for reading and writing.
This small cut at the top is also known as read/write slot.
Original disk was 8 inch size and thereafter the popular size of disk was 5.25 inch, but personally only 3.5 inch size disk are available in the market.
As mentioned above, surface of disk are coated with millions of small iron particles to store the data.
These particles act as magnets which are used to store data in binary form.
A floppy disk, when inserted in the floppy drive, rotates in the drive and normal rotational speed of floppy is 300rpm and Read/ Write head of drive can do the linear motion only.
How data is stored on floppy disk?
§ Magnetic material of disk, which stores the data, is divided into concentric circles known as tracks.
§ The Tracks are further divided into sectors.
§ Each sector has unique number on the disk which helps computer system to access or store the data on floppy disk.
§ Sectors are ultimately used to store or refer data on disk.
§ Presently 3.5 inch floppy is double sided with 80 tracks per side and 18 sectors per track with 512 bytes on every sector.
How Operating System Read Data or Floppy is used for Reading and Writing Purpose?
§ Whenever anyone wants to use a new floppy in a computer; it has to be formatted before its use.
§ But now-a-days most of the floppy comes as pre-formatted, so one can start using them directly in a computer.
§ In fact, the formatting is done to organise the floppy into some areas, so that all the files and records on floppy can be maintained in proper manner.
§ Every Storage device before their use in a computer has to be formatted so that the device storage area can be organised as per the requirement of operating system for that computer.
§ In formatting of a floppy, following four areas or records are created:
§ Boot Record
§ File Allocation Table
§ Root Folder
§ Data Area
· This is the record during formatting of a disk and it maintains information whether the disk is bootable or not.
· That is whether the disk maintains operating system files for start of computer.
· If disk has operating system files then this record maintains the locations of those operating system files on disk.
· Boot Record also maintains some other information like number of bytes per sector and sectors per track, which help operating system to access the data area of disk.
File Allocation Table:
· This is the most important area created duting formatting of a disk.
· This area maintains addresses of files stored on disk in the data area that files stored on a floppy.
· We all know that whenever we want to store any information in a computer, we create a file for that information.
· The address of this created file, in-terms of its location on disk, is maintained in the File Allocation Table (FAT).
· So, Whenever Operating System wants to acess any file, the OS get file’s address information from FAT table, and provide immediate access of the required file.
· FAT area also provides information to operating system regarding available free area on disk for storage of new files, which ultimately help OS in the efficient storage of data.
· A User cannot access FAT area to check the available free tracks and sectors or stored files on disk.
· But user can use Folder or Directory feature/command to check the stored files and available free space on disk.
· A Folder maintains the files and other sub-folders/files in a hierarchical form, and provides a tree view of stored files and folders on disk.
· As the mentioned above, In FAT description, a user can view the stored files and available space on disk using folder or directory feature/command, which provide organized view of files and folders on a disk, in a hierarchical form.
· The top folder of this hierarchical arrangement is known as Root Folder.
· Root Folder is starting folder that organized all the other files and folders under it in a hierarchical form on the disk.
· C: for hard disk, A: for floppy disk, E:for CD/DVD, etc are examples of Root Folders.
· The part of disk that remains free after Boot Record, FAT and Root Folder is known as Data Area.
· This is the largest area on disk and store all the data files and programs on disk.
· Floppy Disk is an inexpensive storage media and provides both sequential and direct access to data at high speed.
· Floppy Disk was the most popular portable storage medium till the popularity of Compact Disk (CD).
· Floppy Disk has lost its popularity as auxiliary storage media to low cost, more reliable and higher capacity CD.