floppy disk

A hard disk uses rigid rotating platters (disks). Each platter has a planar magnetic surface on which digital data may be stored. Information is written to the disk by transmitting an electromagnetic flux through an antenna or read-write head that is very close to a magnetic material, which in turn changes its polarization due to the flux. The information can be read by a read-write head which senses electrical change as the magnetic fields pass by in ...

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Hard disk, Hard disk - Mechanics, Hard disk - Access and interfaces, Hard disk - Other characteristics, Hard disk - Addressing modes, Hard disk - Manufacturers, Hard disk - Firms that have come and gone, Hard disk - Marketing capacity versus true capacity, Hard disk - Hard disk usage, Hard disk - History, Hard disk - Timeline of capacity and other technical improvements, Hard disk - 1950s, Hard disk - 1960s, Hard disk - 1970s, Hard disk - 1980s, Hard disk - 1990s, Hard disk - 2000s, Hard disk - Derivative technologies

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The 1541 used a bit-serial version of the IEEE-488 interface, the speedier parallel version of which was used on Commodore's earlier drives for the PET/CBM range of personal/business computers. To ensure a ready supply of inexpensive cabling for its home computer peripherals, Commodore chose standard DIN connectors for the serial interface. Disk drives and other peripherals such as printers were connected to the computer via a daisy-chain schem ...

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Commodore 1541, Commodore 1541 - Introduction and early problems, Commodore 1541 - Versions and third-party clones, Commodore 1541 - The serial computer interface, Commodore 1541 - Copy protection by read error, Commodore 1541 - The drive head misalignment issue, Commodore 1541 - Commodore's successor products

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Calculator - Origin: The Abacus. Main article: Abacus The first calculators were abacuses, and were often constructed as a wooden frame with beads sliding on wires. Abacuses were in use centuries before the adoption of the written Arabic numerals system and are still widely used by merchants and clerks in China and elsewhere.

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Calculator, Calculator - Overview, Calculator - Electronic calculators, Calculator - A basic calculator, Calculator - Advanced electronic calculators, Calculator - Use in education, Calculator - Other concerns on useage, Calculator - Calculators vs. computing, Calculator - History, Calculator - Origin: The Abacus, Calculator - The 17th century, Calculator - 1930s to 1960s, Calculator - 1970s to mid-1980s, Calculator - Mid-1980s to present, Calculator - Trivia, Calculator - Patents

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A user is issued a credit card after an account has been approved by the credit provider (often a general bank, but sometimes a captive bank created to issue a particular brand of credit card, such as American Express Centurion Bank), with which they will be able to make purchases from merchants accepting that credit card up to a preestablished credit limit. When a purchase is made, the credit card user agrees to pay the card issuer. Originally the user would indicate his/her consent to pay, by signing a receipt with a record of the c ...

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Credit card, Credit card - How they work, Credit card - The merchant's side, Credit card - Secured credit cards, Credit card - Features, Credit card - Security, Credit card - Profits and losses, Credit card - History, Credit card - Controversy, Credit card - Credit card numbering, Credit card - Credit cards in ATMs, Credit card - Credit card networks, Credit card - Collectible credit cards

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The development process of a game varies depending on the company and project. However development of a commercial game usually includes the following stages. Game development - Pre-production. Normally before development on any game can begin a pitch must be made and given a "green light." Who has to give their approval depends on the developer. In the (rather frequent) case in which developer and publisher are separate companies, the pitch must be made to management, approved and then it needs to ...

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Game development, Game development - Overview, Game development - Roles, Game development - The development process, Game development - Pre-production, Game development - Production, Game development - Milestones, Game development - Nearing completion, Game development - Maintenance, Game development - Culture, Game development - Duration, Game development - Locales, Game development - Stability, Game development - Indie game development, Game development - Making your own games, Game development - 3D games

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Disk formatting - Low-level formatting. Warning: The below information on low-level formatting of floppy disks may be technically incorrect. The process is most easily seen with a standard 1.44MB PC floppy disk. Low-level formatting of the floppy normally writes 18 sectors of 512 bytes each on each of 160 tracks (80 on each side) of a floppy disk. That provides 1,474,560 bytes of storage on the floppy. This means that the actual storage capacity of the disk is 1.40625MB. (Sectors are actually larger ...

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Disk formatting, Disk formatting - Formatting a floppy disk, Disk formatting - Low-level formatting, Disk formatting - High-level formatting, Disk formatting - Formatting a hard disk drive, Disk formatting - Low-level formatting

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Except for CP/M and early versions of MS-DOS, each of these operating systems assign drive letters according to the following algorithm: Assign the drive letter 'A' to the boot floppy, and 'B' to the secondary floppy Assign a drive letter, beginning with 'C' to the first active primary partition recognized upon the first physical hard disk Assign subsequent drive letters to the first primary partition upon each successive physical hard disk drive, if present within the system. Assign subsequent drive l ...

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Drive letter assignment, Drive letter assignment - Operating systems that use drive letter assignment, Drive letter assignment - Order of assignment, Drive letter assignment - Common assignments

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Several variants were built; the first system was based on an Intel 80386DX processor running at a clock speed of 16 MHz, with the option of adding an 80387 FPU, featured one or two megabytes of RAM (with a possible maximum of 6 MB), one or two 3.5" floppy disk drives and a single-speed CD-ROM drive. It was delivered with a gamepad, a mouse and a microphone. The operating system used was a graphical OS called Towns OS, based on MS-DOS and the Phar Lap DOS extender (RUN386.EXE). Most games for the system were written in protected ...

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FM Towns, FM Towns - Details, FM Towns - Graphics, FM Towns - Sound

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Electronic organ - The spinet organ. Following World War II, most electronic home organs were built in a configuration usually called a spinet organ, which first appeared in 1949. These compact and relatively inexpensive instruments became the natural successors to the reed organs. They were marketed as competitors of home pianos and often aimed at would-be home organists who were already pianists (hence the name "spinet," a small upright piano). The instrument's design reflected this concept: the spinet organ ph ...

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Electronic organ, Electronic organ - Early history, Electronic organ - The 1950s and 1960s, Electronic organ - The spinet organ, Electronic organ - The chord organ, Electronic organ - The console organ, Electronic organ - Frequency divider organs, Electronic organ - The modern electronic organ

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In the early days of computers, there were no disk drives; delay lines, punched cards, paper tape, magnetic tape, magnetic drums, were used instead. And in the early days of microcomputers, paper tape or audio cassette tape (see Kansas City standard) or nothing were used instead. In the latter case, program and data entry was done at front panel switches directly into memory or through a computer terminal / keyboard, sometimes controlled by a ROM BASIC interpreter; when power was turned off after running ...

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Disk operating system, Disk operating system - History, Disk operating system - Examples of disk operating sytems that were extensions to the OS, Disk operating system - Examples of Disk Operating Sytems that were the OS itself

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The Datassette contained built-in A/D converters and audio filters to convert the computer's digital information into analog sound and vice versa (much like a modem does over a telephone line). Connection to the computer was done via a proprietary plug fitting directly with a corresponding part of the computer's circuit board edge. The absence of recordable audio signals on this interface made the Datassette and its few clones the only cassette recorders usable with CBM's machines, until aftermarket c ...

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Datassette, Datassette - Description and history, Datassette - Main models, Datassette - Used with the PET VIC-20 C64/128, Datassette - Used with the C16/116 and Plus/4

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Once viewed as an operating system only computer professionals and aficionados could use, Linux distributions have become user-friendly, with many graphical interfaces and applications. Its market share of desktops is rapidly growing. According to market research company IDC, in 2002, only 25% of servers and 2.8% of desktop computers were already running Linux. However, argued advantages of Linux, such as lower cost, fewer security vulnerabilities [8] , and lack of vendor lock-in, have spurred a growing number of high-profile cases of ...

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Linux, Linux - History, Linux - Licensing, Linux - Pronunciation, Linux - Linux and GNU/Linux, Linux - Litigation, Linux - Distributions, Linux - Development efforts, Linux - Applications, Linux - Usability and market share, Linux - Installation, Linux - Demonstration, Linux - Configuration, Linux - Running Windows applications, Linux - Programming on Linux, Linux - Portability of Linux, Linux - Support, Linux - General, Linux - Lists, Linux - Magazines, Linux - Videos

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Currently there are three competing formats for rewritable DVDs: DVD-RAM, DVD+RW and DVD-RW. DVD-RAM is more suited to data backups and use in camcorders than DVD±RW. Long life — without physical damage, data is retained for 30 years minimum. Can be rewritten over 100,000 times (DVD±RW can be rewritten approx. 1,000 times). No DVD burning software required – discs can be used and accessed like a removable hard disk. Windows XP and Mac OS(8.6 or later) supports DVD-RAM directly; earlier vers ...

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DVD-RAM, DVD-RAM - Specification, DVD-RAM - Comparison

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Aside from being the first personal computer, the Datapoint 2200 has another connection to computer history. Its original design called for a single-chip 8-bit microprocessor for the CPU, rather than a conventional processor built from discrete TTL modules. In 1969, CTC contracted two companies, Intel and Texas Instruments, to make the chip. TI was unable to make a reliable part and dropped out. Intel was unable to make CTC's deadline. Intel and CTC renegotiated their contract, ending up with CTC keep ...

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Datapoint 2200, Datapoint 2200 - Technical description, Datapoint 2200 - The seed of the x86 architecture, Datapoint 2200 - Credits, Datapoint 2200 - Specifications

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The Cat was primarily the brainchild of Jef Raskin, originator of the Macintosh project at Apple in 1979. It featured a text user interface, not making use of any mouse, icons, or graphics. All data was seen as a long "stream" of text broken into several pages. Instead of using a traditional command line interface or menu system, the Cat made use of its special keyboard, with commands being activated by holding down a "Use Front" key and pressing another key. The Cat also used special "Leap keys" and, by typing strings of characters, the user could navigate to the next occ ...

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Canon Cat, Canon Cat - Description, Canon Cat - History

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CD-ROMs are read using CD-ROM drives and written with CD recorders (often referred to as "burners"). CD-ROM drives—now almost-universal on personal computers—may be connected to the computer via an IDE (ATA) interface, a SCSI interface or a proprietary interface, such as the Panasonic CD interface. Most CD-ROM drives can also play audio CDs and Video CDs with the right software. CD-ROMs are writen and read using hills and valleys on the disc that are microscopic. Each hill represents a 1 and each valley represents a 0See also:

CD-ROM, CD-ROM - Manufacture, CD-ROM - Capacity, CD-ROM - CD-ROM drives, CD-ROM - Copyright Issues, CD-ROM - Data Formats

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Read-only memory - Semiconductor based. Classic mask-programmed ROM chips are written to during production and cannot change content afterwards. But there are other types of non-volatile solid-state memory: PROMs (Programmable Read-Only Memory) can be written to (programmed) via a special device, a PROM programmer. The writing often takes the form of permanently destroying or creating internal links (fuses or antifuses) with the result that a PROM can only be programmed once. EPROMs ( ...

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Read-only memory, Read-only memory - Applications, Read-only memory - Types of ROMs, Read-only memory - Semiconductor based, Read-only memory - Other technologies, Read-only memory - Speed of ROMs, Read-only memory - Reading speed, Read-only memory - Writing speed, Read-only memory - EEPROM/EAROM lifetime, Read-only memory - ROM images

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IBM - Early years. IBM's history dates back decades before the development of electronic computers – before that it developed punched card data processing equipment. It originated as the Computing Tabulating Recording (CTR) Corporation, which was incorporated on June 15, 1911 in Binghamton, New York. This company was a merger of the Tabulating Machine Corporation, the Computing Scale Corporation and the International Time Recording Company. The president of the Tabulating Machine Corporation at that time was He ...

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IBM, IBM - Current business activities, IBM - Culture, IBM - Diversity and workforce issues, IBM - History, IBM - Early years, IBM - World War II, IBM - Airforce and airline projects, IBM - Successes of the 1960s, IBM - Recent history, IBM - Facts and trivia, IBM - Acquisitions, IBM - Spinoffs, IBM - Projects, IBM - BlueEyes, IBM - alphaWorks, IBM - Gaming Chips, IBM - Corporate governance

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Retronym - Retronymic adjectives. Analog/analogue  Describes non-digital devices: analog clock, analog recording. Conventional, classic, or traditional  Describes devices or methods that have been largely replaced or significantly supplemented by new ones. For example, conventional (non-microwave) oven. I, Senior, the Elder  When a dynastic ruler has or adopts a name ident ...

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Retronym, Retronym - Examples, Retronym - Retronymic adjectives

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The machine was based around a Z80B CPU clocked at 6 MHz, and contained an ASIC that is comparable to the Spectrum's ULA. The basic model had 256 KB of RAM, upgradable internally to 512 KB and externally with an additional 4 MB (added in 1 MB packs). Tapes were the original storage medium, but one or two 3.5 inch floppy disk drives could be fitted internally. Six channel, 8 octave stereo sound was provided by a Philips SAA 1099 chip. The ASIC also included a line triggered interrupt counter, allowing video effects to be synchronised t ...

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SAM Coupé, SAM Coupé - Hardware overview, SAM Coupé - Video memory problems, SAM Coupé - Disk drives, SAM Coupé - Expansion ports, SAM Coupé - Kaleidoscope, SAM Coupé - ZX Spectrum compatibility, SAM Coupé - Commercial fortunes, SAM Coupé - Miles Gordon Technology plc., SAM Coupé - SAM Computers Ltd, SAM Coupé - West Coast Computers, SAM Coupé - SAM the robot, SAM Coupé - Notable software, SAM Coupé - Flash!, SAM Coupé - Software houses, SAM Coupé - Enigma Variations, SAM Coupé - Revelation, SAM Coupé - FRED Publishing, SAM Coupé - The SAM Community, SAM Coupé - Screenshots

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Self-modifying code can be used for various purposes: Optimisation of a state dependent loop. Runtime code generation, or specialisation of an algorithm in runtime or loadtime (which is popular, for example, in the domain of real-time graphics). Altering of inlined state of an object, or simulating the high level construction of closures. Patching of subroutine address calling, as done usually at load time of dynamic libraries. Whether this is regarded as 'self-modifying code' or not is a case of terminology. See also:

Self-modifying code, Self-modifying code - Usage of self-modifying code, Self-modifying code - Self-modifying code used to optimize a state-dependent loop, Self-modifying code - Attitudes towards self-modifying code, Self-modifying code - Self-modifying code used as camouflage, Self-modifying code - Operating systems and self-modifying code, Self-modifying code - Just-in-time compilers, Self-modifying code - Interaction of cache and self-modifying code, Self-modifying code - Henry Massalin's Synthesis Kernel

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JVC - 1920s - 1960s. JVC was founded in 1927 as "The Victor Company of Japan" as a subsidiary of the United States' leading phonograph and record company, the Victor Talking Machine Company. In the 1930s JVC were producing phonographs and records. In 1932 JVC started producing radios, and in 1939 JVC debuted Japan's first TV. The Japanese company severed relations with its foreign partners during World War II. In 1929 majority ownership was transferred to RCA-Victor. In 1939 JVC debuted Japan's first televisions. Since 1953, JVC has been owned by Matsushita, and today they own ...

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JVC, JVC - History, JVC - 1920s - 1960s, JVC - 1970s - 1980s, JVC - Present, JVC - Brand name

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