HOME TheInfoList.com
Providing Lists of Related Topics to Help You Find Great Stuff

picture info

EPROM
An EPROM
EPROM
(rarely EROM), or erasable programmable read-only memory, is a type of memory chip that retains its data when its power supply is switched off. Computer memory
Computer memory
that can retrieve stored data after a power supply has been turned off and back on is called non-volatile. It is an array of floating-gate transistors individually programmed by an electronic device that supplies higher voltages than those normally used in digital circuits. Once programmed, an EPROM
EPROM
can be erased by exposing it to strong ultraviolet light source (such as from a mercury-vapor light)
[...More...]

picture info

Optical Disc
In computing and optical disc recording technologies, an optical disc (OD) is a flat, usually circular disc which encodes binary data (bits) in the form of pits (binary value of 0 or off, due to lack of reflection when read) and lands (binary value of 1 or on, due to a reflection when read) on a special material (often aluminium[1] ) on one of its flat surfaces. The encoding material sits atop a thicker substrate (usually polycarbonate) which makes up the bulk of the disc and forms a dust defocusing layer. The encoding pattern follows a continuous, spiral path covering the entire disc surface and extending from the innermost track to the outermost track
[...More...]

picture info

Dekatron
In electronics, a Dekatron
Dekatron
(or Decatron, or generically three-phase gas counting tube or glow-transfer counting tube or cold cathode tube) is a gas-filled decade counting tube. Dekatrons were used in computers, calculators and other counting-related products during the 1950s and 1960s. "Dekatron," now a generic trademark, was the brand name used by Ericsson Telephones Limited (ETL), of Beeston, Nottingham (not to be confused with the Swedish TelefonAB Ericsson
Ericsson
of Stockholm).A dekatron in operation.The dekatron was useful for computing, calculating and frequency-dividing purposes because one complete revolution of the neon dot in a dekatron means 10 pulses on the guide electrode(s), and a signal can be derived from one of the ten cathodes in a dekatron to send a pulse, possibly for another counting stage
[...More...]

Paper Data Storage
Paper
Paper
data storage refers to the use of paper as a data storage device. This includes writing, illustrating, and the use of data that can be interpreted by a machine or is the result of the functioning of a machine. A defining feature of paper data storage is the ability of humans to produce it with only simple tools and interpret it visually. Though this is now mostly obsolete, paper was once also an important form of computer data storage.Contents1 History 2 Limits 3 See also 4 References 5 External linksHistory[edit] Before paper was used for storing data, it had been used in several applications for storing instructions to specify a machine's operation. The earliest use of paper to store instructions for a machine was the work of Basile Bouchon
Basile Bouchon
who, in 1725, used punched paper rolls to control textile looms. This technology was later developed into the wildly successful Jacquard loom
[...More...]

picture info

Hard Disk Drive
A hard disk drive (HDD), hard disk, hard drive or fixed disk[b] is a data storage device that uses magnetic storage to store and retrieve digital information using one or more rigid rapidly rotating disks (platters) coated with magnetic material. The platters are paired with magnetic heads, usually arranged on a moving actuator arm, which read and write data to the platter surfaces.[2] Data is accessed in a random-access manner, meaning that individual blocks of data can be stored or retrieved in any order and not only sequentially. HDDs are a type of non-volatile storage, retaining stored data even when powered off.[3][4][5] Introduced by IBM
IBM
in 1956,[6] HDDs became the dominant secondary storage device for general-purpose computers by the early 1960s. Continuously improved, HDDs have maintained this position into the modern era of servers and personal computers
[...More...]

picture info

Magnetic Tape
Magnetic tape
Magnetic tape
is a medium for magnetic recording, made of a thin, magnetizable coating on a long, narrow strip of plastic film. It was developed in Germany
Germany
in 1928, based on magnetic wire recording. Devices that record and play back audio and video using magnetic tape are tape recorders and video tape recorders. A device that stores computer data on magnetic tape is known as a tape drive. Magnetic tape
Magnetic tape
revolutionized broadcast and recording. It allowed radio, which had always been broadcast live, to be recorded for later or repeated airing. It allowed gramophone records to be recorded in multiple parts, which were then mixed and edited with tolerable loss in quality
[...More...]

picture info

Core Rope Memory
Core rope memory
Core rope memory
is a form of read-only memory (ROM) for computers, first used in the 1960s by early NASA Mars space probes and then in the Apollo Guidance Computer
Computer
(AGC) designed and programmed by the Massachusetts Institute of Technology
Massachusetts Institute of Technology
(MIT) Instrumentation Lab and built by Raytheon. Contrary to ordinary coincident-current magnetic-core memory, which was used for random access memory (RAM) at the time, the ferrite cores in a core rope are just used as transformers. The signal from a word line wire passing through a given core is coupled to the bit line wire and interpreted as a binary "one", while a word line wire that bypasses the core is not coupled to the bit line wire and is read as a "zero"
[...More...]

picture info

Silicon
Silicon
Silicon
is a chemical element with the symbol Si and atomic number 14. It is a hard and brittle crystalline solid with a blue-grey metallic lustre; and it is a tetravalent metalloid and semiconductor. It is a member of group 14 in the periodic table: carbon is above it; and germanium, tin, and lead are below it. It is relatively unreactive. Because of its high chemical affinity for oxygen, it was not until 1823 that Jöns Jakob Berzelius
Jöns Jakob Berzelius
was first able to prepare it and characterize it in pure form. Its melting and boiling points of 1414 °C and 3265 °C respectively are the second-highest among all the metalloids and nonmetals, being only surpassed by boron. Silicon
Silicon
is the eighth most common element in the universe by mass, but very rarely occurs as the pure element in the Earth's crust
[...More...]

picture info

Disk Pack
Disk packs and disk cartridges were early forms of removable media for computer data storage, introduced in the 1960s.Contents1 Disk pack 2 Disk cartridge 3 Alignment 4 References 5 See alsoDisk pack[edit] Disk pack
Disk pack
manufactured by Nashua, USA, without its protective cover. A 3.5" modern hard drive is shown for comparison.A Disk pack
Disk pack
is a layered grouping of hard disk platters (circular, rigid discs coated with a magnetic data storage surface). A disk pack is the core component of a hard disk drive. In modern hard disks, the disk pack is permanently sealed inside the drive. In many early hard disks, the disk pack was a removable unit, and would be supplied with a protective canister featuring a lifting handle. The protective cover consisted of two parts, a clear plastic shell, with a handle in the center, that enclosed the top and sides of the disks and a separate bottom that completed the sealed package
[...More...]

Mellon Optical Memory
Mellon optical memory was an early form of computer memory invented at the Mellon Institute
Mellon Institute
(today part of Carnegie Mellon University) in 1951.[1][2] The device used a combination of photoemissive and phosphorescent materials to produce a "light loop" between two surfaces. The presence or lack of light, detected by a photocell, represented a one or zero. Although promising, the system was rendered obsolete with the introduction of core memory in the early 1950s. It appears that the system was never used in production.Contents1 Description1.1 Writing 1.2 Reading2 ReferencesDescription[edit] The main memory element of the Mellon device consisted of a very large (television sized) square vacuum tube consisting of two slightly separated flat glass plates. The inner side of one of the plates was coated with a photoemissive material that released electrons when struck by light
[...More...]

picture info

Field-effect Transistor
The field-effect transistor (FET) is a transistor that uses an electric field to control the electrical behaviour of the device. FETs are also known as unipolar transistors since they involve single-carrier-type operation. Many different implementations of field effect transistors exist. Field effect transistors generally display very high input impedance at low frequencies
[...More...]

picture info

Intel
Coordinates: 37°23′16.54″N 121°57′48.74″W / 37.3879278°N 121.9635389°W / 37.3879278; -121.9635389 Intel
Intel
Corporation Intel
Intel
Corporation's current logo, used since 2006Intel's headquarters in Santa Clara, Cali
[...More...]

picture info

Ultraviolet
Ultraviolet
Ultraviolet
(UV) is an electromagnetic radiation with a wavelength from 100 nm to 400 nm, shorter than that of visible light but longer than X-rays. UV radiation is present in sunlight constituting about 10% of the total light output of the Sun. It is also produced by electric arcs and specialized lights, such as mercury-vapor lamps, tanning lamps, and black lights. Although long-wavelength ultraviolet is not considered an ionizing radiation because its photons lack the energy to ionize atoms, it can cause chemical reactions and causes many substances to glow or fluoresce. Consequently, the chemical and biological effects of UV are greater than simple heating effects, and many practical applications of UV radiation derive from its interactions with organic molecules. Suntan and sunburn are familiar effects of over-exposure of the skin to UV, along with higher risk of skin cancer
[...More...]

picture info

Magnetic-core Memory
Magnetic-core memory
Magnetic-core memory
was the predominant form of random-access computer memory for 20 years between about 1955 and 1975. Such memory is often just called core memory, or, informally, core. Core uses tiny magnetic toroids (rings), the cores, through which wires are threaded to write and read information. Each core represents one bit of information. The cores can be magnetized in two different ways (clockwise or counterclockwise) and the bit stored in a core is zero or one depending on that core's magnetization direction. The wires are arranged to allow for an individual core to be set to either a one or a zero and for its magnetization to be changed by sending appropriate electric current pulses through selected wires. The process of reading the core causes the core to be reset to a zero, thus erasing it. This is called destructive readout
[...More...]

picture info

Drum Memory
Drum memory
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. For many early computers, drum memory formed the main working memory of the computer. It was so common that these computers were often referred to as drum machines.[3] Some drum memories were also used as secondary storage.[4] Drums were displaced as primary computer memory by magnetic core memory which was a better balance of size, speed, cost, reliability and potential for further improvements.[5] Similarly, drums were replaced by hard disk drives for secondary storage, which were also less expensive and denser. The manufacture of drums ceased in the 1970s.Contents1 Design 2 Use and legacy 3 See also 4 Notes 5 References 6 External linksDesign[edit] A drum memory contained a large metal cylinder, coated on the outside surface with a ferromagnetic recording material
[...More...]

FJG RAM
FJG RAM, short for Floating Junction Gate Random Access Memory, is a type of computer memory invented by Oriental Semiconductor Co., Ltd. The FJG RAM has an ultra-compact cell area of 4F2 (F refers to feature size) and a capacitorless cell configuration. It is made without exotic process steps, materials or new process tools, and the process for making the device is available from all existing DRAM
DRAM
fabs. Due to the absence of a capacitor, the FJG cell process is more compatible with logic process, allowing its use not only in standalone DRAM applications but also in embedded- DRAM
DRAM
applications
[...More...]

.