Storage media types are the main aspects of functioning. Material media. Graduation writing assignment
Over the course of its existence, human civilization has found many ways to record information. Its volumes are growing every year. For this reason, the media are also changing. It is this evolution that will be discussed below.
Remnants of the past
The most ancient monuments of human activity can be considered rock paintings that depict animals that were targets of hunting. The first material storage media were of natural origin.
A real breakthrough can be considered the appearance of writing among the Sumerians, who lived in modern Iraq and used not stone, but clay tablets, which were fired after writing. Thus, their safety increased significantly. However, the speed at which knowledge was recorded was extremely slow.
You can also note Egyptian papyrus, wax, skins, on which they first began to write in Persia. In Asia, bamboo and silk were used. The ancient Indians had a unique knotted writing system. In Rus', birch bark was in use, which archaeologists still find today.
Paper
Paper media have made a revolution, the scale of which is difficult to overestimate. Despite the fact that the first analogues of cellulose material were obtained by the Chinese back in the 2nd century, it became publicly available only in the 19th century.
The appearance of books is also associated with paper. In the 1450s, a German inventor invented a manual printing press, with which he published two copies of the Bible. These events served as the starting point for a new era of mass book printing. It was thanks to him that knowledge ceased to be the lot of a thin layer of humanity, but became accessible to everyone.
Today's paper can be newsprint, offset, coated, etc. Its choice depends on specific purposes. And although white linen is in demand more than ever, it has already lost its innovative position.
Punched cards and paper tapes
Information media received the next impetus in their development at the beginning of the 19th century, when the first cardboard punch cards appeared. Holes were placed in certain places through which data was read. The technology was initially used to control
Interest in the new product increased after it began to be used in the United States to more conveniently and quickly calculate the results of the country's census in 1890. The production of cards was carried out by IBM, which in the future became a pioneer of computer technology. The heyday of technology occurred in the middle of the 20th century. It was then that the systematizing and generalizing a variety of data began to spread.
The first computer storage media were also punched paper tapes. They were made from paper and used in telegraphs. Due to their format, tapes allowed for easy input and output. This made them indispensable until the advent of magnetic competitors.
Magnetic tape
No matter how good the previous external storage media were, they could not reproduce what they recorded. This problem was solved with the advent of magnetic tape. It was a flexible base covered with several layers on which information was recorded. Various chemical elements acted as the working medium: iron, cobalt, chromium.
Magnetic storage media have made a breakthrough in sound recording. It was this innovation that allowed the new technology to quickly take root in Germany in the 30s. Previous devices (phonographs, gramophones, gramophones) were mechanical in nature and were not practical. Reel-to-reel and cassette tape recorders have become widespread.
In the 50s, attempts were made to use these developments as computer storage media. Magnetic tapes were introduced into personal computers in the 80s. Their popularity was generally due to such advantages. such as large capacity, comparatively low cost of production and low energy consumption.
The disadvantage of the tapes is the shelf life. Over time they become demagnetized. In the best case, data is stored for 40 - 50 years. However, this did not stop the format from becoming popular all over the world. It is worth mentioning separately about video cassettes, the heyday of which occurred at the end of the 20th century. Magnetic storage media have become the basis for a new type of television and radio broadcasting.
Hard drives
Meanwhile, the development of the industry continued. Large-volume information media required modernization. The first hard drives or hard drives were created in 1956 by IBM. However, they were impractical. They were larger than a box and weighed almost a ton. At the same time, the volume of stored data did not exceed 3.5 megabytes. However, the standard subsequently developed, and by 1995 the 10 gigabyte limit was surpassed. And after another 10 years, Hitachi models with a capacity of 500 gigabytes appeared on sale.
Unlike flexible analogues, hard drives contained aluminum plates. The data is reproduced via read heads. They do not touch the disk, but work at a distance of several nanometers from it. One way or another, the operating principle of hard drives is similar to the characteristics of tape recorders. The main difference lies in the physical materials used to manufacture the devices. Hard drives have become the basis of personal computers. Over time, such models began to be produced together with storage devices, drives and an electronics unit.
In addition to the main memory needed to hold data, hard drives have a certain buffer needed to smooth out read speeds from the device.
3.5" floppy disks
At the same time, there was progress in the field of small formats. Knowledge of magnetic properties was useful in creating floppy disks, the data from which was read using a special disk drive. The first such analogue was presented by IBM in 1971. The recording density on such information media was up to 3 megabytes. The basis of the floppy disk was a flexible disk, covered with a special layer of ferromagnets.
The main achievement - the reduction in the physical size of the media - has made this format the main one on the market for a quarter of a century. In the US alone in the 80s, up to 300 million new floppy disks were produced annually.
Despite a lot of advantages, the new product also had disadvantages - sensitivity to magnetic influences and low capacity compared to the ever-increasing needs of the average computer user.
CDs
The first generation of optical media was CDs. Their prototype was gramophone records. However, new external storage media were made from polycarbonate. The disk of this substance received the thinnest metal coating (gold, silver, aluminum). To protect the data, it was coated with a special varnish.
The notorious CD was developed by Sony and put into mass production in 1982. First of all, the format gained wild popularity due to its convenient sound recording. A volume of several hundred megabytes made it possible to displace first vinyl players, and then tape recorders. If the former were inferior in the amount of information, the latter had worse sound quality. In addition, the new format consigned floppy disks to the past, which not only held less data, but were also not very reliable.
CDs sparked the personal computing revolution. Over time, all the industry giants (for example, Apple) switched to producing PCs along with drives that support the CD format.
DVD and Blue-Ray
First-generation optical information media did not last long at the Olympus of data storage. In 1996, a DVD appeared, which was six times larger in volume than its ancestor. The new standard made it possible to record longer videos. The film industry quickly adapted to it. Movies on DVD have become widely available all over the world. The principle of operation and encoding of information remains the same compared to CDs.
Finally, in 2006, a new, currently latest format for optical storage media was launched. The volume began to amount to hundreds of gigabytes. This ensures better quality audio and video recording.
Format wars
Over the past few years, conflicts between incompatible information storage formats have become more frequent. At the next stage of industry development, external media from different manufacturers are competing with each other for a monopoly in the format.
One of the first such examples is the conflict between Edison’s phonograph and Berliner’s gramophone in the 10s of the 20th century. Subsequently, similar disputes arose between compact cassettes and 8-track audio cassettes; VHS and Betamax; MP3 and AAC, etc. The latest in this series was the “war” between HD DVD and Blue-Ray, which ended in victory for the latter.
Flash drives
Examples of storage media cannot be complete without mentioning USB flash drives. The first Universal Serial Bus was developed in the mid-90s. Today, there is already a third generation of this bus, which allows you to connect a peripheral device to a personal computer. And although this problem existed long before the advent of USB, it was only solved in the last decade.
Today, every computer has a recognizable socket with which you can connect a mobile phone, player, tablet, etc. to the computer. Fast data transfer of any format has made USB a truly universal tool.
The most popular based on this interface are flash drives or, in common parlance, flash drives. Such a device has a USB connector, a microcontroller, a chip, and an LED. All these details made it possible to keep gigabytes of information in one pocket. In its own way it is inferior even to floppy disks, which had a capacity of 3 megabytes. The volume of devices where information is stored has increased significantly. Storage media, on the contrary, tend to shrink physically.
The versatility of the connector allows drives to work not only with personal computers, but also with TVs, DVD players and other devices with USB technology. A huge advantage compared to optical analogues was less susceptibility to external influences. A flash drive is not afraid of scratches and dust, which were a mortal threat to CDs.
Virtual reality
In recent years, computer storage media have been losing ground to virtual alternatives. Since today it is easy to connect a PC to the Global Network, information is stored on shared servers. The amenities are undeniable. Now, to access their files, the user does not need physical media at all. To interact with data from a distance, it is enough to be within the range of a wireless Wi-Fi connection, etc.
In addition, this phenomenon helps to avoid misunderstandings with the failure of physical drives that are vulnerable to damage. Remote servers, communication with which is supported by the signal, will not be affected, and in case of unforeseen situations, there are backup data storage facilities there.
Conclusion
Throughout history - from cave paintings to virtual bits - people have strived to make information media larger, more reliable and more accessible. This desire has led to the fact that today we live in an era that is not without reason called the age of the information society. Progress has reached the point where people are now simply drowning in the flow of data in their daily lives. Perhaps information carriers, the types of which are constantly multiplying, will change radically, according to the requirements of modern man.
Introduction page 3
Modern material carriers of documented information, their classification and characteristics
I. Modern material media p. 5
II. Classification of modern material media p. 6
III. Characteristics of modern material media
1. Magnetic media page 9
2. Plastic cards page 12
3. Optical media p. 13
4. Flash storage media p. 17
5. 3D image media p. 19
Conclusion page 23
References page 26
Introduction
The concept of document is central, fundamental in the conceptual system of document management. This concept is widely used in all areas of public activity. Almost every branch of knowledge has one or several versions for its understanding in accordance with the specifics of those objects that are given the status of a document.
The concept of document acts as a generic concept for specific types: published, unpublished, film, sound, photographic document, etc. from this point of view, the following types of document are: booklet, drawing, map, film, magnetic tape, magnetic and optical disk.
Let us recall once again the definition of a document: information fixed on a material medium in a stable symbolic form in a man-made way for its transmission in space and time. From the definition it follows that the document does not exist in finished form, it needs to be created, i.e. fix in a stable form. The process of fixing (fixing) information on a tangible medium is called documentation.
In the process of documentation, social information is transformed from one symbolic form to another, i.e. coding of information, without which it is impossible to implement the basic functions of a document - the functions of consolidating and transmitting information in space and time.
Informatization of society, the rapid development of micrography, computer technology and its penetration into all spheres of activity determined the appearance of documents on the latest storage media. The presence of a general concept of a document does not exclude the possibility of the existence of more private, highly specialized interpretations of it in relation to various spheres of social activity and scientific disciplines: source study, record keeping, diplomacy, computer science, legal science.
Among these new media, the group of “Modern media of documented information” stands out, which are currently used, replacing older media with increasing popularity. For example, it seems that not so long ago a very common storage medium - a flexible magnetic disk or floppy disk is practically not used, it was replaced by optical disks and media based on flash memory, the same phenomenon is happening in audio and video technology, audio and video cassettes have been replaced optical disks.
This topic “Modern material storage media, their classification and characteristics” also concerns document and communication activities, as it examines the means that simplify the exchange of information.
I believe that the topic of my course work is relevant at the present time, since knowledge and ability to use modern media allows us to keep up with the times and speed up the process of creating and transmitting information in space and time, as well as improve the conditions for storing documented information.
Modern material carriers of documented information, their classification and characteristics
I. Modern material media
The informatization of society, the rapid development of computer technology and its penetration into all spheres of human activity determined the appearance of documents in modern, non-traditional, i.e. non-paper media.
The concepts of “modern” and “non-traditional” document are largely arbitrary and serve to name a group of documents that, unlike traditional ones, i.e. paper ones, as a rule, require modern technical means to reproduce information. All this is connected with the advent of electronic computers - computers, which are complexes of technical means designed to automatically convert information, used to record and reproduce both text, graphic, audio and video information.
The emergence of modern media is also due to the fact that over half a century of its existence there have already been five generations of computers, and from generation to generation their productivity and storage capacity have increased by an order of magnitude or more. And also new, more advanced peripheral devices appeared - printers, scanners, copiers, and now multifunctional devices (MFPs) are increasingly used, which facilitate the work of office workers, allowing them to obtain a hard copy of a document not only from the computer’s memory, but from modern media .
From my point of view, modern media for documented information include: magnetic cards, magnetic hard drives, optical discs, holograms, flash memory-based media. This may not be the correct judgment, but these media are actively used at present. They replaced the well-known audio, video cassettes, microforms, floppy disks or floppy disks. They can be called outdated. The same thing will happen with modern media, because they are modern at the moment. In ten years, modern media will be replaced by even more modern media, since humanity does not stand in one place, but is progressing and developing at a rapid pace. And in ten years, the modern material carriers of documented information discussed in this work will be called obsolete.
II . Classification of modern material media
A document is a dual unity of information and a material medium. Therefore, important features (“strong differences”) that can be used as the basis for classification are the structural features and shape of the material on which information is recorded. In particular, according to this criterion, the entire variety of documents contained on modern material media can be represented as a class:
· documents on an artificial material basis (on polymer materials).
In turn, documents on an artificial material basis can be classified as multilayer, in which there are at least two layers - a special working layer and a substrate (magnetic media, optical disks, etc.). In this case, the base substrate can be of any kind - paper, metal, glass, ceramic, wood, fabric, film or plastic plate. From one to several (sometimes up to 6-8) layers are applied to the base. As a result, the material carrier sometimes appears in the form of a complex polymer system.
There are also energy carriers.
According to the form of the material storage medium, documents can be:
· card (plastic cards);
· disk (disc, compact disc, CD-ROM, video disc). The information is placed on concentric tracks – optical discs.
Depending on the possibility of transporting material media, documents can be divided into:
· stationary (hard magnetic disk in a computer);
· portable (optical disks, flash memory-based media).
Depending on the method of documentation, documents on modern storage media can be divided into:
· magnetic (magnetic hard drives, magnetic cards);
· optical (laser) – documents containing information recorded using a laser-optical head (optical, laser discs);
· holographic – created using a laser beam and a photo-recording layer of a material carrier (hologram).
· documents on computer media – electronic documents created using media and recording methods that ensure the processing of its information by an electronic computer.
Documents on modern tangible media, as a rule, cannot be directly perceived or read. Information is stored on computer media, and some documents are created and used directly in machine-readable form.
In terms of intended perception, the documents in question are classified as machine readable. These are documents designed to automatically reproduce the information contained in them. The content of such documents is fully or partially expressed by signs (matrix arrangement of characters, numbers, etc.) adapted for automatic reading. Information is recorded on magnetic tapes, cards, disks and similar media.
Documents on modern storage media belong to the class of technically encoded ones, containing a recording that can be reproduced only with the help of technical means, including sound reproducing, video reproducing equipment or a computer.
Based on the nature of the connection between documents and technological processes in automated systems, the following are distinguished:
· a machine-oriented document intended for recording the reading of part of the information contained in it using computer technology (filled out special forms, forms, questionnaires, etc.);
· machine-readable document, suitable for automatic reading of the information contained in it using a scanner (text, graphic);
· a document on a machine-readable medium, created by computer technology, recorded on a machine-readable medium: hard magnetic disk, optical disk, flash memory-based medium - and executed in the prescribed manner;
· a document-machineogram (printout), created on paper using computer technology and executed in the prescribed manner;
· a document on the display screen, created by computer technology, reflected on the display screen (monitor) and executed in the prescribed manner;
· an electronic document containing a set of information in the memory of a computer, intended for human perception using appropriate software and hardware.
III . Characteristics of modern material media
1. Magnetic media
Of all the carriers of magnetic documents, I would like to highlight the magnetic disk - an information carrier in the form of a disk with a ferromagnetic coating for recording. Magnetic disks are divided into hard disks (hard drives) and floppy disks (floppy disks).
From this group, in my work I will consider only hard drives, since floppy disks, which I call obsolete storage media, have been practically replaced by optical disks and flash memory-based media.
Hard drives
Hard magnetic disks, called hard drives, are designed for permanent storage of information used when working with a personal computer and are installed inside it.
Hard drives are significantly superior to floppy disks. They have the best characteristics of capacity, reliability and speed of access to information. Therefore, their use ensures high-speed characteristics of the dialogue between the user and the programs being implemented, expands the system capabilities for using databases, organizing multitasking modes of operation, and provides effective support for the virtual memory mechanism. However, the cost of hard drives is much higher than the cost of floppy disks.
The hard drive is mounted on a spindle axis driven by a special motor. It contains from one to ten disks (platters). The engine speed for conventional models can be 3600, 4500, 5400, 7200, 10000 or even 12000 rpm. The disks themselves are ceramic or aluminum plates processed with high precision, on which a magnetic layer is applied.
The most important part of the hard drive is the read-write head. As a rule, they are located on a special positioner (head actuator). To move the positioner, predominantly linear motors (such as voice coils) are used. Several types of heads are used in hard drives: monolithic, composite, thin-film, magnetoresistive (MR, Magneto-Resistive), as well as heads with enhanced magnetoresistive effect (GMR, Giant Magneto-Resistive). The magnetoresistive head, developed by IBM in the early 1990s, is a combination of two heads: a thin-film write head and a magnetoresistive read head. Such heads make it possible to increase the recording density by almost one and a half times. The GMR head can further increase the recording density.
Inside any hard drive there is always an electronic board that deciphers the commands of the hard drive controller, stabilizes the engine rotation speed, generates signals for the write heads and amplifies them from the read heads.
There are two types of hard magnetic disks.
Hard disk (hard disk) is a built-in storage device (disk drive) on a hard magnetic disk, a package of magnetic disks fixed one above the other, the removal of which during operation of electronic computers is impossible.
A removable hard disk is a package of magnetic disks enclosed in a protective shell, which during operation of electronic computers can be removed from the drive on a removable hard disk and replaced with another. The use of these disks provides a virtually unlimited amount of external computer memory.
During the so-called low-level formatting procedure, information is written to the hard drive that determines the layout of the hard drive into cylinders and sectors. The format structure includes various service information: synchronization bytes, identification headers, parity bytes. In modern hard drives, such information is recorded once during the manufacture of the hard drive. Damage to this information due to independent low-level formatting can lead to complete inoperability of the disk and the need to restore this information to factory conditions.
The capacity of a hard drive is measured in megabytes. By the end of the 1990s, the average capacity of hard drives for desktop systems reached 15 gigabytes, and servers and workstations with a SCSI interface use hard drives with a capacity of over 50 gigabytes. Most modern personal computers use hard drives with a capacity of 40 gigabytes.
One of the main characteristics of a hard drive is the average time during which the hard drive finds the necessary information. This time is usually the sum of the time required to position the heads on the desired track and wait for the required sector. Modern hard drives provide access to information in 8-10 ms.
Another characteristic of a hard drive is the read and write speed, but it depends not only on the disk itself, but also on its controller, bus, and processor speed. For standard modern hard drives this speed is 15-17 MB/s.
2. Plastic cards
Plastic cards are a device for magnetic storage and data management.
Plastic cards consist of three layers6 of a polyester base, on which a thin working layer is applied, and a protective layer. Polyvinyl chloride is usually used as a base, which is easy to process and resistant to temperature, chemical and mechanical influences. However, in a number of cases, the basis for magnetic cards is pseudoplastic - thick paper or cardboard with double-sided lamination.
The working layer (ferromagnetic powder) is applied to the plastic using hot stamping in the form of separate narrow strips. Magnetic strips, according to their physical properties and scope of application, are divided into two types: high-ercivity and low-ercivity. High-ercivity stripes are black. They are resistant to magnetic fields. To record them, higher energy is needed. Used as credit cards, driver's licenses, i.e. in cases where increased wear resistance and security are required. Low-ercivity magnetic stripes are brown in color. They are less secure, but they are easier and faster to record. They are used on cards with a limited validity period, in particular for travel in the metro.
It should be noted that, in addition to magnetic, there are other ways to record information on a plastic card: graphic recording, embossing (mechanical extrusion), barcoding, laser recording. In particular, electronic chips have recently begun to be increasingly used in plastic cards instead of magnetic stripes. Such cards, in contrast to simple magnetic ones, began to be called intelligent or smart cards (from the English smart - smart). The microprocessor built into them allows you to store a significant amount of information, makes it possible to make the necessary calculations in the system of banking and trade payments, thus turning plastic cards into multifunctional storage media.
According to the method of access to the microprocessor (interface), smart cards can be:
· with a contact interface (i.e., when performing a transaction, the card is inserted into the electronic terminal;
· with a dual interface (can operate both contact and contactless, i.e. data exchange between the card and external devices can be carried out via a radio channel).
The protective layer of magnetic plastic cards consists of a transparent polyester film. It is designed to protect the working layer from wear. Sometimes coatings are used to protect against counterfeiting and copying. The protective layer provides up to two tens of thousands of write and read cycles.
The sizes of plastic cards are standardized. In accordance with the international standard ISO-7810, their length is 85.595 mm, width - 53.975 mm, thickness - 3.18 mm.
The scope of application of plastic and pseudo-plastic magnetic cards is quite extensive. In addition to banking systems, they are used as a compact information carrier, identifier for automated accounting and control systems, identification, pass, telephone and Internet cards, and transport tickets.
3. Optical media
The continuous scientific and technical search for material carriers of documented information with high durability, large information capacity with minimal physical dimensions of the medium has led to the emergence of optical disks, which have recently become widespread. They are plastic or aluminum discs designed to record or reproduce sound, images, alphanumeric and other information using a laser beam.
Standard CDs are 120 mm (4.75 in) in diameter, 1.2 mm (0.05 in) thick, with a 15 mm (0.6 in) center hole. They have a rigid, very durable transparent, usually plastic (polycarbonate) base 1mm thick. However, it is possible to use other materials as a base, for example, an optical medium with a cardboard base.
The working layer of optical disks was initially made in the form of thin films of low-melting materials (tellurium) or alloys (tellurium-selenium, tellurium-carbon, tellurium-lead, etc.), and later - mainly based on organic dyes. Information on a CD is recorded on the working layer in the form of a spiral track using a laser beam, which acts as a signal converter. The path goes from the center of the disk to its periphery.
As the disk rotates, the laser beam follows a track whose width is close to 1 micron, and the distance between two adjacent tracks is up to 1.6 microns. The marks (pits) formed on the disk by a laser beam have a depth of about five billionths of an inch and an area of 1-3 microns 2. The internal recording diameter is 50 mm, the external one is 116 mm. The total length of the entire spiral path on the disk is about 5 km. There are 625 tracks for every mm of disk radius. In total, the disk contains 20 thousand turns of a spiral track.
To ensure good reflection of the laser beam, the so-called “mirror” coating of the disks with aluminum (in regular disks) or silver (in recordable and rewritable disks) is used. A thin protective layer of polycarbonate or a special varnish with high mechanical strength is applied to the metal coating, on top of which drawings and inscriptions are placed. It must be borne in mind that it is this painted side of the disk that is more vulnerable than the opposite side, from which information is read through the entire thickness of the disk.
The manufacturing technology of optical discs is quite complex. First, a glass matrix is created - the basis of the disk. For this purpose, plastic (polycarbonate) is heated to 350 degrees, then it is “injected into the mold, instantly cooled and automatically fed to the next technological operation. A photorecording layer is applied to the original glass disc. In this layer, a Pit system is formed by the laser recording system, i.e. a primary “master disk” is created. Then, mass replication and creation of copy disks are carried out using the “master disk” by injection molding.
The information capacity of disks is usually less than 650 MB. Several hundred thousand pages of typewritten text can be recorded on one disk. For comparison: the entire book collection of the Russian State Library, if transferred to CDs, can fit in an ordinary three-room apartment. Meanwhile, optical disks with a much larger capacity have already been developed - over 1 GB.
Since recording and playback of information on optical discs are contactless, the possibility of mechanical damage to such discs is virtually eliminated.
It, like a magnetic document, belongs to modern information carriers based on optical methods of recording, reading and playback. Optical documents include optical discs and video discs: compact discs, CD-ROM, DVD.
Scheme of the design of an optical video disc: 1 - outer layer of transparent plastic; 2 - metallized reflective recording track; 3 - hard opaque plastic base.
Information is written and read onto an optical disc using a focused laser beam.
Depending on the ability to be used for recording and reading, optical discs are divided into two types:
1. WORM (Write Once Read Many) – drives designed for recording information and storing it;
2. CD-ROM (Compact Disk Read Only Memory) - drives designed for reading information.
Optical discs can be divided into types:
· An audio CD is a disk with permanent (non-erasable) audio information recorded in binary code;
· CD-ROM is a disk with permanent memory designed for storing and reading significant amounts of information. It contains computer information that is read by a disk drive connected to the PC;
· Video CD – a disk on which text, visual and audio information, as well as computer programs, are digitally recorded;
· DVD disc is a type of new generation of optical discs on which text, video and audio information, as well as computer data, are digitally recorded;
· Magneto-optical disk – disks consisting of various combinations of a floppy magnetic disk, hard drive and optical disk.
4. Flash storage media
One of the most modern and promising carriers of documented information is solid-state flash memory, which is a microcircuit on a silicon crystal. This is a special type of non-volatile rewritable semiconductor memory. The name refers to the enormous erasing speed of the flash memory chip.
To store information, flash media does not require additional energy, which is needed only for recording. Moreover, compared to hard drives and CD-ROM media, recording information on flash media requires tens of times less energy, since there is no need to operate mechanical devices, which consume most of the energy. Maintaining an electrical charge in flash memory cells in the absence of electrical power is achieved using the so-called floating gate transistor.
Flash memory-based media can store recorded information for a very long time (from 20 to 100 years). Being packaged in a durable, hard plastic case, flash memory chips can withstand significant mechanical loads (5-10 times higher than the maximum permissible for conventional hard drives). The reliability of this type of media is also due to the fact that they do not contain mechanically moving parts. Unlike magnetic, optical and magneto-optical media, it does not require the use of disk drives using complex precision mechanics. They are also distinguished by silent operation.
In addition, these media are very compact.
Information on flash media can be changed, i.e. rewrite. In addition to media with a single write cycle, there is flash memory with a number of allowable write/erase cycles up to 10,000, as well as from 10,000 to 100,000 cycles. All these types are not fundamentally different from each other.
Despite their miniature size, flash cards have a large memory capacity of many hundreds of MB. They are universal in their application, allowing you to record and store any digital information, including music, video and photographic information.
Flash memory has become one of the main storage media widely used in various digital multimedia devices - laptop computers, printers, digital voice recorders, cell phones, electronic watches, notebooks, televisions, air conditioners, MP3 players, digital photo and video cameras.
Flash cards are one of the most promising types of material carriers of documented information. A new generation of cards has already been developed - Secure Digital, which have cryptographic information protection capabilities and a highly durable housing that significantly reduces the risk of damage to the media by statistical electricity.
Cards with a capacity of 4 GB have been released. They can hold about 4,000 high-resolution photos, or 1,000 songs in MP3 format, or a full DVD movie. Meanwhile, the use of a flash card with a capacity of 8 GB is gaining momentum.
The production of so-called fixed flash drives with a capacity of hundreds of MB has been launched, which are also a device for storing and transporting information.
Thus, the improvement of flash memory technology is moving in the direction of increasing the capacity, reliability, compactness, versatility of media, as well as reducing their cost.
5. Three-dimensional image media
Hologram is a modern medium of three-dimensional image.
It is a document containing an image, the recording and reproduction of which is carried out optically using a laser beam without the use of lenses.
A hologram is created using holography - a method of accurately recording, reproducing and transforming wave fields. It is based on wave interference - a phenomenon observed during the addition of transverse waves (light, sound, etc.) or when waves are amplified at some points of the document and weakened at others, depending on the phase difference of the interfering waves. Simultaneously with the “signal” wave scattered by the object, a “reference” wave from the same light source is sent to the photographic plate. The pattern that appears during the interference of these waves, containing information about the object, is recorded on a photosensitive surface (hologram). When a hologram or a section of it is irradiated by a reference wave, a three-dimensional image of the object can be seen.
The peculiarity of holography is the creation of a visual image of an object that has all the characteristics of the original. In this case, a complete illusion of the presence of the object is achieved.
On a hologram, information is recorded and reproduced using a laser. The quality of the image depends on the monochromaticity of the laser radiation and the resolution of the photographic materials used to obtain holograms. If the laser radiation spectrum is wide, then the resulting interference pattern will not be clear and blurry. Therefore, when producing holograms, lasers with a very narrow spectral line of radiation are used. The quality of the holographic image is affected by shooting conditions and the resolution of photographic materials. Externally, the hologram resembles an exposed photographic negative, on which there are no signs of the “photographed” object. However, it is enough to illuminate the hologram with a laser beam and a three-dimensional image appears. Objects are located in the depths of the photographic plate, like a reflection in a mirror.
With the help of holography, it is possible to obtain such three-dimensional images that create a complete illusion of the reality of the observed objects - a visual sensation of volume and color, including all shades of color and angle. In a hologram, the image of an object is so perfect and believable that the observer perceives it as a real object.
A hologram can be flat or three-dimensional. The larger the volume of the hologram (the thickness of the photosensitive film), the better all its properties are realized.
A hologram differs from an ordinary photograph in the same way as a sculpture differs from a painting. In ordinary photography, the image point on the photographic plate corresponds to some point on the object. In holography, each point of an object emits a scattered wave that hits the entire surface of the hologram. As a result, any point of the object corresponds to the entire surface of the hologram: if you disassemble the photographic plate on which the hologram is recorded, any part of it is enough to reconstruct the image of the scattering object in three dimensions. This is reminiscent of a lens breaking. Using any of its fragments you can get an image of an object.
Holography uses the coherence property of a laser beam: the wave surface (wave front) of a certain beam is recorded in the form of interference fringes on a photosensitive material or photographic plate, which is called a hologram. When reading the hologram, the original wavefront is restored. In other words, the laser beam is split into two beams, one of which is projected onto the photographed object, and, reflected from this object, the light hits the photosensitive material; the second beam is directly projected onto the photosensitive material.
Using these two beams, an interference pattern is recorded. When a laser beam is projected onto the manufactured hologram, a three-dimensional image of the photographed object pops up. This process is called recovery. If you examine the hologram through a microscope, you will see a system of alternating light and dark stripes. The interference pattern of real objects is very complex.
A hologram can also be made in another way, thanks to which a three-dimensional image can be seen in ordinary light.
Since a hologram allows you to record an image down to the phase components of a light beam, it can store three-dimensional information about the object being photographed. Currently, this technology is used in bar code readers, optical disc cartridges, and can also be successfully used to convert information in optical computers.
Most of the methods being developed and implemented for holographic registration and processing of information arrays most often take the form of printed documents. A hologram is an optical element that forms an image without the help of external optics, which is the most important advantage. Up to 150 images can be applied to one hologram, and these images do not interfere with each other during their reproduction. You just need to respect the angle at which each image was recorded. The hologram is noise-resistant; damage to some part of it does not lead to the loss of the entire image. Since each point of the object is recorded over almost the entire area of the hologram, scratches, dust, and foreign inclusions in the emulsion cause only minor deterioration of the image and a decrease in its brightness.
A square centimeter of film surface can contain 100 million bits of information. And on a potassium-bromine plate measuring 2.5*2.5*0.2 cm, you can record about 300 thousand images of documentary information, approximately the entire archive of a large library.
The invention of holograms is of great importance. Developing computing technology requires long-term storage devices with large amounts of memory. Electronic memory successfully copes with this work. But holographic memory systems are even more suitable for these purposes. The capacity of holographic memory can be 10 6 – 10 8 bits. Within microseconds, it selects data from memory cells.
Conclusion
Having considered this topic, we can say that with the development of science and technology, new information carriers will appear, more advanced ones, which will displace the outdated information carriers that we use now.
The widespread use of optical disks is associated with a number of their advantages compared to magnetic media, namely: high reliability during storage, a large amount of stored information, recording audio, graphics and alphanumeric information on one disk, search speed, economical means of storing and providing information , they have a good quality/price ratio.
As for hard drives, no computer has yet managed without them. In the development of hard drives, the main trend is clearly visible - a gradual increase in recording density, accompanied by an increase in spindle head rotation speed and a decrease in information access time, and ultimately - an increase in performance. The creation of new technologies is constantly improving this media; it changes its capacity to 80 - 175 GB. In the longer term, a carrier is expected to appear in which individual atoms will play the role of magnetic particles. As a result, its capacity will be billions of times higher than currently existing standards. There is also one advantage: lost information can be recovered using certain programs.
Improvements in flash memory technology are moving towards increasing the capacity, reliability, compactness, versatility of media, as well as reducing their cost.
Holographic digital storage media with a capacity of up to 200 GB are at the development stage. They have the shape of a disk consisting of three layers. A 0.2 mm thick recording (working) layer and a half-millimeter transparent protective layer with a reflective coating are applied to a glass substrate 0.5 mm thick.
The future development of the document is associated with the computerization of the document and communication system, while traditional types of documents will remain in the information society along with non-traditional types of information media, enriching and complementing each other.
Documents, being a mass social product, are characterized by relatively low durability. During their operation in the operational environment and especially during storage, they are subject to numerous negative influences, and the media are not only subject to damage in the external environment, they are subject to technical (in terms of the level of equipment development) and logical (related to the content of information, software and information security standards ) aging.
In connection with these factors, work is actively underway to create compact carriers that work with atoms and molecules. The packing density of elements assembled from atoms is thousands of times greater than in modern microelectronics. As a result, one CD made using this technology can replace thousands of laser discs.
The rapid development of the latest information technologies thus leads to the creation of ever new, more information-intensive, reliable and affordable carriers of documented information.
Future document specialists must be prepared for this psychologically, theoretically and technologically. We need to keep up with the times, since document management is inextricably linked with computer science, where science does not stand in one place.
Someday in Russia a multifunctional medium will be used that will store information about a person, allowing it to be used simultaneously as a document: identifying an individual, carrying bank card information, medical data about diseases, it can be used in transport, libraries, etc. d. All this will be possible only with the development of document science, computer science, and jurisprudence, and it will depend on people whether they are ready for such global changes.
Literature used:
1. GOST Z 51141-98. Record keeping and archiving. Terms and definitions. M.: Standards Publishing House, 1998.
2. Kushnarenko N.N. Documentation. Textbook. – K.: Zannanya, 2006.
3. Larkov N.S. Documentation. – M.: Vostok-Zapad, 2006.
4. Great Encyclopedia of Cyril and Methodius on DVD. – Ural Electronic Plant LLC, 2007. Persons. VAF No. 77-15
GOST Z 51141-98. Record keeping and archiving. Terms and definitions. M.: Standards Publishing House, 1998.
Kushnarenko N.N. Documentation. – K.: Zannaya, 2006. – P. 432.
Larkov N.S. Documentation. – M.: Vostok-Zapad, 2006. – P. 174.
Great Encyclopedia of Cyril and Methodius on DVD. – Ural Electronic Plant LLC, 2007. Persons. VAF No. 77-15
Kushnarenko N.N. Documentation. – K.: Zannaya, 2006. – P. 451.
Storage medium (data medium) - a material object or environment intended for storing data. Recently, information carriers are mainly called devices for storing data files in computer systems, distinguishing them from devices for input/output of information and devices for processing information.
Classification of storage media
Digital storage media - CDs, floppy disks, memory cards
Analog storage media - tape and reel-to-reel cassettes
By signal shape used to record data, a distinction is made between analog and digital media. To rewrite information from analogue media to digital or vice versa, a signal is required.
By purpose distinguish between carriers
- For use on various devices
- Built into a specific device
In terms of recording stability and re-recordability:
- Read-only storage devices (ROMs) whose contents cannot be changed by the end user (for example, CD-ROM, DVD-ROM). ROM in operating mode allows only reading information.
- Recordable devices in which the end user can write information only once (for example, CD-R, DVD-R, DVD+R, BD-R).
- Rewritable devices (for example, CD-RW, DVD-RW, DVD+RW, BD-RE, magnetic tape, etc.).
- Operating devices provide a mode for recording, storing and reading information during its processing. Fast but expensive RAM (SRAM, static RAM) are built on the basis of flip-flops, slow but cheap varieties (DRAM, dynamic RAM) are built on the basis of a capacitor. In both types of RAM, information disappears after disconnection from the current source. Dynamic RAM requires periodic content updating - regeneration.
According to physical principle
- perforated (with holes or cutouts) - punched card, punched tape
- magnetic - magnetic tape, magnetic disks
- optical - optical discs CD, DVD, Blu-ray Disc
- magneto-optical - compact disc magneto-optical (CD-MO)
- electronic (use semiconductor effects) - memory cards, flash memory
According to design (geometric) features
- Disk (magnetic disks, optical disks, magneto-optical disks)
- Tape (magnetic tape, punched tape)
- Drum (magnetic drums)
- Card (bank cards, punched cards, flash cards, smart cards)
Sometimes information carriers are also called objects, reading information from which does not require special devices - for example paper media.
Storage media capacity
The capacity of a digital medium means the amount of information that can be recorded on it; it is measured in special units - bytes, as well as their derivatives - kilobytes, megabytes, etc., or in kibibytes, mebibytes, etc. For example, the capacity of common CD media is 650 or 700 MB, DVD-5 - 4.37 GB, double-layer DVD 8.7 GB, modern hard drives - up to 10 TB (as of 2009).
Storage medium– physical environment that directly stores information. The main carrier of information for a person is his own biological memory (the human brain). A person’s own memory can be called operative memory. Here the word “operative” is synonymous with the word “fast”. Memorized knowledge is reproduced by a person instantly. We can also call our own memory internal memory, since its carrier - the brain - is located inside us.
Storage medium- a strictly defined part of a specific information system that serves for intermediate storage or transmission of information.
The basis of modern information technology is the computer. When it comes to computers, we can talk about storage media as external storage devices (external memory). These storage media can be classified according to various criteria, for example, by type of execution, material from which the media is made, etc. One of the options for classifying information carriers is presented in Fig. 1.1.
List of storage media in Fig. 1.1 is not exhaustive. We will look at some storage media in more detail in the following sections.
Information storage- is a way of disseminating information in space and time. The method of storing information depends on its medium (book - library, painting - museum, photograph - album). This process is as ancient as the life of human civilization. Already in ancient times, people were faced with the need to store information: notches in trees so as not to get lost while hunting; counting objects using pebbles and knots; depictions of animals and hunting episodes on cave walls.
A computer is designed for compact storage of information with the ability to quickly access it.
Information system is an information repository equipped with procedures for entering, searching, placing and issuing information. The presence of such procedures is the main feature of information systems, distinguishing them from simple accumulations of information materials.
disk file drive information
TAPE MEDIA
Magnetic tape- a magnetic recording medium, which is a thin flexible tape consisting of a base and a magnetic working layer. The operating properties of magnetic tape are characterized by its sensitivity during recording and signal distortion during recording and playback. The most widely used is multilayer magnetic tape with a working layer of needle-shaped particles of magnetically hard powders of gamma iron oxide (y-Fe2O3), chromium dioxide (CrO2) and gamma iron oxide modified with cobalt, usually oriented in the direction of magnetization during recording.
DISK MEDIA
Disk storage media refer to direct access machine media. The concept of direct access means that the PC can “access” the track on which the section with the required information begins or where new information needs to be written.
Disk drives are most diverse:
Floppy magnetic disk drives (FMD), also known as floppy disks, also known as floppy disks
Hard magnetic disk drives (HDDs), also known as hard drives (popularly just “screws”)
Optical CD drives:
CD-ROM (Compact Disk ROM)
There are other types of disk storage media, for example, magneto-optical disks, but due to their low prevalence we will not consider them. Floppy disk drives
Some time ago, floppy disks were the most popular means of transferring information from computer to computer, since the Internet in those days was very rare, computer networks too, and devices for reading and writing CDs were very expensive. Floppy disks are still used today, but quite rarely. Mainly for storing various keys (for example, when working with a client-bank system) and for transmitting various reporting information to government supervisory services.
Diskette- a portable magnetic storage medium used for repeated recording and storage of relatively small data.
This type of media was especially common in the 1970s and early 2000s. Instead of the term “floppy disk”, the abbreviation GMD is sometimes used - “flexible magnetic disk” (accordingly, a device for working with floppy disks is called NGMD - “floppy magnetic disk drive”, the slang version is flopdrive, flopik, flopper from the English floppy-disk or in general " cookie"). Typically, a floppy disk is a flexible plastic plate coated with a ferromagnetic layer, hence the English name “floppy disk”. This plate is placed in a plastic case that protects the magnetic layer from physical damage. The shell can be flexible or durable. Floppy disks are written and read using a special device - a floppy drive. A floppy disk typically has a write-protect feature that allows read-only access to the data. The appearance of a 3.5" floppy disk is shown in Fig. 1.2.
The search for information, its accumulation and systematization are important information processes that contribute to understanding the surrounding reality. These are the processes necessary to satisfy human information needs, to make decisions and acquire new knowledge. The materials in this section will help you understand the importance of systematization and storage processes when creating, replenishing and maintaining information arrays, wisely selecting modern information media, acquiring new knowledge using a variety of information systems, accumulating and structuring information in the network space.
A storage medium is any material object or medium used to store and receive information.
Modern storage media
The informatization of society and the widespread use of information and communication technologies have determined the emergence of new types of information media - “modern”. These are media that are directly related to the invention of electronic computers, mobile communications and telecommunications networks. They are designed to store and present text, audio, video, graphic information and multimedia.
What media are known to history? Initially, people recorded information on sand and earth, then on stone (rocks, cave walls), and later with the help of clay and wax tablets. For many decades, parchment scrolls and papyrus existed. The inconvenience of storing and accessing information and the fragility of media have contributed to the search for new ways to store information. Only in the VIII-IX centuries. (in Rus' in the 15th century) thanks to the Arabs, paper was invented. For many centuries, the book took a leading position in matters of preservation and presentation of information.
All paper-based storage media are usually called “traditional” or “paper”.
In the context of an expanded information and communication educational space, when almost everyone has a personal computer or mobile device with access to the global Internet, new ways of storing information have emerged. The easiest way is to store all the necessary information on the computer. To do this, information in the form of files is usually structured into thematic folders, forming a system of multi-level attachments (folder directory). The advantages of this method are simplicity (just click on the “save” button while working) and speed (saving any information in any size occurs quickly).
However, it is worth remembering that this choice also has a number of disadvantages. Firstly, it is unreliable. A computer's hard drive (HDD - Hard Disk Drive) can be formatted, infected with viruses, or simply fail due to external factors. Secondly, the most important drawback in the dynamic world around us is the lack of mobility. It is not always possible to carry a laptop with you, which means that information loses its accessibility.
Another way to store information is in local networks(LAN - Locate Area Network). A local network connects computers installed in the same room (for example, a computer lab) or in the same building (school, university). Through access to the file server, the opportunity is provided for both individual and joint (simultaneous) use of data, applications, and programs stored there.
A popular way of storing information today is use of removable storage media(or alienated).
External hard drive. This is a portable storage device with a storage capacity of up to 10 TB, with high speed of writing and reading information, and has a USB port for easy connection to a technical device. It is a hard magnetic disk enclosed in a shock-resistant case. This is a necessary thing if you need to store and process a lot of videos, or work with the same information on different technical devices.
In the 1970-1990s. floppy disk was popular diskette) with 5.25" (maximum capacity 1.2 MB) and 3.5" (1.44 MB) formats. Nowadays floppy disks are not used due to their low capacity.
Today, common storage media are optical or laser discs. Based on the recording method, laser discs are divided into CD-R and DVD-R and are read-only; they often contain educational programs, game programs, and electronic textbooks. Information can only be written to CD-R and DVD-R discs once; data cannot be deleted. Information can be recorded multiple times on CD-RW and DVD-RW discs. DVDs (English) Digital Versatile Disc) are a continuation of the development of CD discs (English) Compact Disc). They are similar in appearance, but DVDs can store much more information due to the use of a laser with a shorter wavelength when recording. Based on the data structure, DVDs come in four types: DVD-Video, DVD-Audio and DVD-Data. Today, CDs and DVDs are the most “long-lived” storage media.
HD DVD (English) High-Definition/Density) is a high-definition optical disc recording technology developed by Toshiba, NEC and Sanyo, using standard-sized discs (120 mm in diameter) and a blue-violet laser for recording. With the advent of Blu-ray technology, a competitor appeared Blu-ray Disc, BD(Blu-ray - from English, blue ray and disc - disk) - an optical media format used for recording and storing digital data, including high-definition video with increased density.
The most popular storage medium currently is USB. flash drive(“flash drive”). This is a compact electronic storage device used to store digital information on flash memory and connects to a computer or other reading device via a standard USB connector.
Despite the constant miniaturization of case sizes, the design of a flash drive can be a real work of art.
Memory cards are widely used in electronic devices, including digital cameras, cell phones, laptops, MP3 players and game consoles. Main varieties memory cards- Memory Stick Pro, SD (Secure Digital), SD, SDHC and SDXC. MiniSD and MicroSD (or TransFlash) - their smaller versions, are the standard for most cell phones, communicators and GPS navigators.
Promising types of storage media include media based on nanotechnology. However, perhaps in the future we will not need storage media at all, all data will be stored on the Internet. Have existed for a long time network file sharing services. For example, video services (video.mail.ru, servisvideo, rutube, youtube, myvi.ru, smotri.com); audio services (prod, studio, odeo, itunesstore, last.fm, soundcloud, zvooq, Google Music, Yandex.Music); photo services (flickr, flamber, panoramio, picasa, fotodia), where you can post relevant information, discuss and exchange files.
To ensure that your files are available to you and your colleagues on any computer or mobile device, you should contact cloud data storage (cloud services)- (Dropbox, Google Drive, Mega, Yandex.Disk, Copy.com, [email protected], Adrive). Each user on the network is provided with disk space to store personal and collectively created materials.
