(Hard Disk Drive Technology)
Group 3: Instructor:
Tyrone James Dumandan Mr. Allen Paul Aclan Chrysolite Nocon
Renz Niño Mercado
BSCpE 102 – B
Disk Drive or Hard Disk Drive
A disk drive is a randomly addressable and rewritable storage device. The term can be broadly interpreted to include optical drives and in earlier times, floppy drives. However, in popular usage, it has come to relate mainly to hard disk drives (HDDs). Disk drives can either be housed internally within a computer or housed in a separate box that is external to the computer. They are found in PCs, servers, laptops and storage arrays, for example. They work by rotating very rapidly around a head or heads, which read and write data. They differ from solid state drives (SSDs), which have no moving parts and offer greater performance, but also cost more and generally offer less capacity.
History of hard disk drive
Hard disks were invented in the 1950s. They started as large disks up to 20 inches in diameter holding just a few megabytes. They were originally called "fixed disks" or "Winchesters" (a code name used for a popular IBM product). A hard disk drive consists of a motor, spindle, platters, read/write heads, actuator, frame, air filter, and electronics. The first computer with a hard disk was IBM’s RAMAC, which was used during the 1960 Olympics to calculate sports results. A bit later, in 1962, removable disk packs were developed – a forerunner of the floppy disk. In 1964, the CRC algorithm was introduced. It provided greater security by checking and comparing data before and after it was written to the disk. In 1971, the first 8-inch diskettes came onto the market.
Evolution of Hard Disk Drives
The first hard disk drive, like so many innovations in computing, came from IBM. It was called the IBM Model 350 Disk File and was a huge device. It had 50 24-inch diskscontained inside a cabinet that was as large as a cupboard and anything but lightweight. This hulk of a storage unit could store a whopping 5 MB of data.
Above: An IBM Model 350 Disk File being delivered. Yes, that’s ONE hard disk drive unit. Although hard disk drives kept improving, state-of-the art disks were built according to the concept “bigger is better” well into the ‘80s. Hard disk drives were normally used together with big mainframe computers, so this was not such a big deal. Entire rooms were already set aside for the computers. Case in point, here below is a 250 MB hard disk drive from 1979.
Above: State-of-the-art hard disk drive from the ‘70s.
IBM introduced the first hard disk drive to break the 1 GB barrier in 1980. It was called the IBM 3380 and could store 2.52 GB (500 times more than the consumer options at the time). Its cabinet was about the size of a refrigerator and the whole thing weighed in at550 pounds (250 kg).
Above: The disk drive module of the IBM 3380.
Early in the ‘80s, smaller “consumer” hard disk drives designed to be used with the increasingly popular microcomputers (now known as PCs) started to appear. The first ones were 5 MB in size and had a form factor of 5.25 inches. For a visual on how hard disk drive sizes have changed since the ‘80s until today, have a look at the below image with an old 8-inch drive all the way down to today’s 3.5-inch, 2.5-inch and 1.8-inch drives.
Above: Three decades of shrinkage
Components of Hard Disk Drive
Disk Case - The rectangular shaped disk case holds all of the components of a hard disk drive. The case is secured by screws and should not be opened outside of a dust-free environment.
Disk Platter - The platter shaped like a record with a magnetic surface. Its job is to store the data contained on the hard disk drive. There can be one or multiple platters depending on the disk capacity. A...
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