Search results
Results from the WOW.Com Content Network
Magnetic storage media, primarily hard disks, are widely used to store computer data as well as audio and video signals. In the field of computing, the term magnetic storage is preferred and in the field of audio and video production, the term magnetic recording is more commonly used. The distinction is less technical and more a matter of ...
A typical magnetic region on a hard-disk platter (as of 2006) is about 200–250 nanometers wide (in the radial direction of the platter) and extends about 25–30 nanometers in the down-track direction (the circumferential direction on the platter), [citation needed] corresponding to about 100 billion bits per square inch of disk area (15.5 ...
The second, Forrester's, was the coincident-current system, which enabled a small number of wires to control a large number of cores enabling 3D memory arrays of several million bits. The first use of magnetic core was in the Whirlwind computer, [19] and Project Whirlwind's "most famous contribution was the random-access, magnetic core storage ...
Magneto-optical disc storage is optical disc storage where the magnetic state on a ferromagnetic surface stores information. The information is read optically and written by combining magnetic and optical methods. Magneto-optical disc storage is non-volatile, sequential access, slow write, fast read storage used for tertiary and off-line storage.
Sequential changes in the direction of magnetization represent binary data bits. The data is read from the disk by detecting the transitions in magnetization. User data is encoded using an encoding scheme, such as run-length limited encoding, [n] which determines how the data is represented by the magnetic transitions.
Hard disk drives store data in the magnetic polarization of small patches of the surface coating on a disk. The maximum areal density is defined by the size of the magnetic particles in the surface, as well as the size of the "head" used to read and write the data. In 1956 the first hard drive, the IBM 350, had an areal density of 2,000 bit/in 2.
Drum memory of a Polish ZAM-41 computer Drum memory from the BESK computer, Sweden's first binary computer, which made its debut in 1953. Drum memory was a magnetic data storage device invented by Gustav Tauschek in 1932 in Austria. [1] [2] Drums were widely used in the 1950s and into the 1960s as computer memory.
Disk storage is now used in both computer storage and consumer electronic storage, e.g., audio CDs and video discs (VCD, DVD and Blu-ray). Data on modern disks is stored in fixed length blocks, usually called sectors and varying in length from a few hundred to many thousands of bytes.