What is a hard drive?
Hard disk (HDD - Hard Disk Drive) isAn electronic storage medium based on the principle of magnetic recording. In most computers, the hard disk is the main data storage device. In this article I'll tell you more about what a hard disk is and what its name means.
Why is the hard drive called hard?
The information stored on the hard disk,recorded on hard plates - magnetic disks made of aluminum or glass and coated with a layer of ferromagnetic material or silica. That's why the hard drive is called hard, as opposed to a flexible electronic magnetic recording information carrier - a floppy disk.
A hard disk is also often called a hard drive. When designing a hard disk, engineers called it briefly 30-30, which meant the use of two 30 MB modules.
Hard disk - how does it work?
The principle of hard disk operation is similar in many respects tothe operation of the tape recorder. The working surface of the disk moves relative to the reading head. When an electric current is applied to the head, it initiates an alternating magnetic field, which in turn acts on the ferromagnet with which the disk is coated, which changes the direction of the magnetization vector of the macroscopic region in the magnetic crystal, this change depending on the field size.
Other types of electronic media
In addition to hard disks today there are othertypes of electronic media - floppy disks, disks and semiconductor carriers (flash drives). The floppy disks have already become almost useless, since they can store very little information, CDs and DVDs are also not very popular, they are mainly used to distribute programs, games, music, etc., but flash drives are now used everywhere.
Internal and portable disks
Hard drives can be either internal orportable. Internal are in the system unit of each computer, and portable are used as a very large flash drive. Portable removable disks can be of all sizes, from a few gigabytes to terabytes.
For additional explanations, you can read the article What is HDD.