Hard Disk Drives

                                                          Hard Disk Drives

              The hard disk is hardly a personal computer invention. The first hard disks, which first showed up in the 1950s on mainframe computers, were 20 inches in diameter and held only a few megabytes of data. Hard disks were originally called "fixed disks" and "Winchester drives" and became known as hard disks later to differentiate them from floppy disks. However, the basic technology used in the earliest hard disks has not changed all that much over the years, although the size and capacity of the drives has.

               It is the main storage device. It consists of all of the computer's item as well as documents created by using all software. It lies inside the system Board (CPU Box). Technically microcomputer hard disks are called or fixed disks, as they are a pack of disks permanently sealed inside a disk drive.

              The sealed case contains platters fixed in place, read/write heads and other part of mechanisms. It over-comes much of the danger of dust, magnetism and fingerprints interfering with the data. the read/write heads do not actually touch the surface of the disk (as floppy disk drives) but fly over it on a cushion of air.