They began developing a disk drive in —made up of a horizontal shaft with eight or more inch magnesium disks. Few sold. The Ferranti Sirius is announced. The Sirius was a small, low-cost business computer using a simple programming language. Its main memory was a magnetostrictive delay line. The medium here was a thin strip of special metal rolled into a coil, with transducers at either end.
Like all delay lines, bits were fed into one end, detected at the other, and continuously recirculated. Although this type of delay line was considered to be somewhat slow, its low cost made it attractive to computer designers. The concept of virtual memory emerges from a team under the direction of Tom Kilburn at the University of Manchester on its Atlas computer.
Virtual memory permitted a computer to use its storage capacity to switch rapidly among multiple programs or users and was a key requirement for timesharing. The mylar cards were suspended from rods that selected and dropped one at a time for processing. Each CRAM deck of cards recorded about 5. Each pack weighed about ten pounds, held six disks, and had a capacity of 2 million characters.
The disks rotated at 1, RPM and were accessed by a hydraulic actuator with one head per disk. The offered some of the advantages of both tapes and disks. Thin-film memory is introduced.
Sperry Rand developed this faster variation on core memory. Small glass plates held tiny dots of magnetic metal film interconnected with printed drive and sense wires.
However, it did find a larger market in military computers and higher end projects where speed was a premium. Several other manufacturers, such as RCA, also developed thin-film memory. DECtape is introduced. DECtape was often used as a form of personal data storage, as the small reels could be easily hand-carried. IBM's disk cartridge is announced. Each consisted of a magnetically coated, direct access disk encased in a plastic cartridge that easily fit into built-in disk drives.
When it was inserted into the disk drive, a power drive engaged the disk and spun it at 1, revolutions per minute. Simultaneously, an arm extended to perform read and write functions on the disk's magnetic surfaces. Wide magnetic strips were plucked from bins and wrapped around a rotating cylinder for reading and writing.
Reliability problems plagued the initial models, but after improvements were made it became relatively reliable and sold until TROS modules preceded solid-state ROM chips, and each bit of this read-only memory for microcode was a little magnetic transformer.
Punches in the mylar strips controlled whether current flowed through the transformer or around it, representing a binary zero or a one. The IBM direct access storage facility is introduced. It was an improvement over the disk storage drive and provided higher data storage density. Eight drives plus a spare with removable 29 MB disk packs shared one control unit.
The extra drive was a spare for the user or could be worked on by a field engineer while the other eight were in use by the customer. Victor Comptometer Corporation produces the Victor desktop calculator. Six bit MOS shift registers built by General Microelectronics provided memory for the calculator, which was the first to use MOS for both logic and memory.
The calculator could perform multiple functions and had a small, integrated CRT display. However, the immature MOS manufacturing process made the parts unreliable, limiting sales. The system could read and write up to a trillion bits of information—the first such system in the world.
The used thin strips of film on which were written data created by an electron beam and a wet photographic development process. The system used sophisticated error correction and a pneumatic robot to move the film strips to and from a storage unit. Only five were built. Unlike hard drives, a user could easily transfer a floppy in its protective jacket from one drive to another. Soon after, it became an industry standard. Apollo Guidance Computer read-only rope memory is launched into space aboard the Apollo 11 mission, which carried American astronauts to the Moon and back.
The DVD was invented and developed by multiple companies in Hewlett-Packard announced it would no longer be manufacturing hard drives, July 10, After 17 years of development, MySQL version 1. By , it would grow to become the database software powering half of all websites on the Internet. Imation developed the SuperDisk drive and diskette, also called the LS It allows data to be written to a specific type of rewritable disc again and again.
The Memory Stick was released by Sony in October The Sony Memory Stick is a memory card that can only be used with Sony devices. It had a storage of capacity of 8 MB and was sold to the public starting in Google began development of Bigtable , a massively-scaling data storage system used internally for its critical applications.
The Blu-ray disc format was developed by multiple companies and introduced to the public on January 4, The basic technology behind laserdiscs was invented all the way back in Above right: Another Laserdisc. The diskette, or floppy disk named so because they were flexible , was invented by IBM and in common use from the mids to the late s. The first floppy disks were 8 inches, and later in came 5.
The first floppy disk, introduced in , had a capacity of A read-write version came a year later. Above left: An 8-inch floppy and floppy drive next to a regular 3. Above right: The convenience of easily removable storage media. Magnetic tape was first used for data storage in The tapes were metal and feet long meters and therefore very heavy. You could store about kB per side on a minute tape. Above left: The standard compact cassette. Above right: The Commodore Datassette is sure to bring up fond memories for people who grew up in the 80s.
DECtape was a magnetic data storage introduced in used mainly with Digital Equipment Corporation computers. The tape was 0. Above right: DECtape removable magnetic media. These were some of the best we could find, and we hope you liked them. The Selectron. The punch card. The punch card reader and writer. Punched tape 1 and 2. Data was stored and retrieved by use of an access arm while the aluminum discs spun at speeds of 1, rpm.
The original iPhone in included up to 8 GB of storage and weighed under one pound. In a computer the size of two refrigerators, you could have stored one individual iPhone picture.
It was restored by two engineers, Dave Bennet and Joe Feng.
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