Harddisk & Storage is a computer device used to store data as a permanent storage. It is made from metal disk and coated with a magnetic substance, which rapidly spins while working. It can be installed to the computer through the motherboard, which has the Parallel ATA interface (PATA), Serial ATA interface (SATA), and Small Computer System Interface (SCSI). Moreover, the external connection can be done through the USB cable or the FireWire cable from Apple, which is rarely known. Also, eSATA, a SATA connector accessible from outside the computer and provides a signal connection for external storage devices, is included. This allows you to use a hard disk more conveniently when you do not own any computer.
The current hard disk was developed in 1956 by the founder of the IBM company, Mr. Renold Johnson. At that time, the harddisk was rather large and has the diameter up to 20 inches with only megabyte capacity. The conversion unit at present is the 1,024 MB, which is equal to 1 GB. At first, it was called a fixed disk. The IBM company called it Winchesters. Later, it was called a Harddisk to categorize and differentiate it from a floppy disk, which is a soft magnetic disk. From the 21st century, the harddisk can normally be found in general electronic devices. Not only can they be found in the computer, but also in any electronic devices such as MP3 player, digital recorder, camera, laptop, PDA, or even some mobile phone models from 2005 (Nokia and Samsung, both companies who mainly manufacture mobile phones with the harddisk).
The principal mechanism of writing data on the hard disk is not different from the cassette tape. They require the writing substance, which is the magnetic substance. The magnetic substance can be erased or written over and over again. When the data are recorded, they can recall the original format for a couple of years. The differences between the hard disk and cassette tape are the following points;
The magnetic substance of the cassette tape is coated on the long plastic strip while in the hard disk, it is coated on a glass or aluminum disk, which is sleek as a mirror. The data storage in hard disk is kept in the form of a magnetic domain, which is very tiny when compared with the domain of magnetic tape. The smaller the domain is, the more capacity the hard disk has, and also the ability to reach data at a shorter period of time.
Nowadays, the desktop PC has a capacity of 60 GB to 4 TB. The data are encrypted in a file format, which consists of data called byte. A byte is an ASCII code and is presented in the form of alphabetic, graphics, video, and sound. The number of bytes gathers to be commands or programs. There is the read/write head of hard disk to interpret and transfer the data to the processor for calculation and interpretation.
The data storage: The data stored on the hard disk are on the sectors and tracks. A track is in a circle shape and sectors are a part of the track. The yellow part represents a track and the red part represents as a sector. Inside the sector, there is a fixed number of bytes, for example, from 256 to 512. It depends on how the computer's operating system manages each section. Several sectors can combine and create clusters. The format process at low-level format will write new tracks and sectors, while high-level format will not do anything to tracks and sectors, but will write FAT-formatted media as disk preparation to data storage.