26.04.2013

When we record valuable data on modern media, we don’t really think about how many years we can count on it. Personal archives, interesting not only to members of the same family, are disappearing into oblivion. In order to understand how to get out of such a situation, it is worth taking a retrospective look at the features of various media and methods of presenting information.

When we write valuable data onto modern media, we don’t really think about how many years we can count on it. Yuri Revich talks about the numbers and deadlines.

Every family at some point has to decide what to do with the collections of vinyl records or tape reels inherited from parents, with rolls of film and albums full of yellowed photographs. Three times in the memory of representatives of the older generation, the physical principles of sound recording changed, and sound media (and, of course, devices for playing them) changed 6 times! Back in the 50s of the last century, these were shellac records (78 rpm), then they were replaced by vinyl “long-playing” discs (33.3 rpm). Almost simultaneously, household reel-to-reel tape recorders appeared, and then cassette tape recorders appeared. In the mid-1980s, all analog devices were replaced en masse by digital optical CDs. And five to ten years ago, universal miniature flash cards appeared, and the main channel for distributing sound recordings in general became intangible entities - files downloaded via the Internet.

Video media changes were made even faster. Film for amateur movie cameras (8- and 16-mm), which became publicly available in the late 1950s and early 1960s, was already replaced by household video cassettes in the VHS format in the 1980s. Consumers had just begun to acquire video libraries on cassettes when DVDs appeared, similar in structure to an audio CD. Eventually, amateur video recording evolved, like sound recording, into compact computer file formats that were easily distributed over the Web.

Many people give up when looking at this diversity - this is how personal archives, interesting not only to members of one family, disappear into oblivion. In order to understand how to get out of such a situation, it is worth taking a retrospective look at the features of various media and methods of presenting information.

Durability of analog media

Oddly enough, the more advanced the media is from a technical point of view, the shorter its service life. AND this rule has almost no exceptions. Books and manuscripts on parchment can last for thousands of years, not to mention clay tablets or inscriptions on stone. True, libraries sometimes burn, and recently the whole world saw with their own eyes that even a stone cannot stand if someone wants to purposefully destroy cultural monuments - in 2001, the Taliban blew up the Bamiyan Buddha statues that had stood for more than one and a half thousand years, justifying this act in in the eyes of the whole world, the invasion of Afghanistan by Western troops.

If we exclude such radical methods of exposure, and protect from moisture, light, rodents and insects, then paper publications published before the beginning of the 19th century can be stored for hundreds of years. At the end of the 18th century, to the chagrin of archivists, a method was invented for making cheap paper from wood using automatic or semi-automatic machines. Such paper is much cheaper than old paper, but it turns yellow and becomes brittle over several decades, and the synthetic dyes on it fade. Moreover, in the light this happens much faster, but “wood” paper deteriorates in any case, regardless of the care of storage, for “internal” reasons.

Interestingly, in the Soviet Union there was a government program to produce durable papers for important documents. By the 1990s, the production of office paper began to be produced, designed to last up to 850 and 1000 years. However, the computer revolution has made the implementation of such a program unnecessary - documents began to be stored on electronic media, which we will return to later.

During the technological revolution of the late 19th to mid-20th centuries, fundamentally new information media appeared, but paper, even degraded by mass production, remained one of the most reliable in this series. The only type of media comparable in durability to paper is black-and-white polyester-based photographic film, which began to be produced around the 1960s. The life of celluloid film produced before is even shorter than that of newsprint. Celluloid contains volatile substances that gradually evaporate over time, causing the film to warp, deform and lose transparency.

The main weakness of analog photography lies in its main component - the gelatin layer. As an example, we can cite the original color photographs of Sergei Prokudin-Gorsky, taken at the beginning of the 20th century, each of which is a set of three color-separated negatives on a glass substrate. They have been stored in the gentle conditions of the Library of Congress (USA) since 1948, but when combining, each of the three colors has to be “tightened” using computer methods - they have become so deformed in less than a hundred years. Gelatin tends to dry out and become deformed over time and, among other things, cannot withstand even low heat. The image on negative films, which, unlike prints, are not subjected to special tanning, can simply be washed off with hot tap water.

Colored dyes in films and prints tend to fade spontaneously even when stored in the dark. Domestic color film, especially those produced before the 1970s and 1980s, is stored for no more than a few decades. In the late 2000s, an unrestored copy of “Prisoner of the Caucasus” was shown on television, which had faded almost completely in less than half a century. This was especially noticeable in episodes with a predominance of light colors.

Tapes are also quite capricious, especially those that store the most valuable and rare recordings of the 1950s and 60s, the time of the emergence of Russian art song and rock, when reel-to-reel tape recorders were still in use in our country for the primitive tape “Type 2". These tapes dry out and crumble - experts advise that before re-recording, let such a reel rest in a sealed bag along with moistened cotton wool (however, you can’t keep tapes in a humid atmosphere for a long time either!). An inherent drawback of all magnetic tapes is the ability to have the so-called copy effect, when the magnetized layer in one turn of the roll is “imprinted” over time in adjacent turns. To reduce this effect, tapes should be stored in refrigerators and rewound occasionally. Keeping at low temperatures is also useful in order to prevent a spontaneous decrease in magnetization due to the thermal movement of atoms in the particles of the magnetic layer.

Frequent use of tapes and films contributes to their rapid wear. Wear during use is generally a characteristic property of analog media. A particularly striking example of this are shellac records of the first half of the twentieth century. On primitive mechanical gramophones they could withstand only a few dozen playback cycles. The force of impact on the media can be judged by the fact that after each play it was necessary to replace the steel needle, which was worn out from friction on the track. Vinyl discs, which replaced shellac, like black-and-white film, can theoretically be stored forever in archives, but also quickly deteriorate when played. It is significant that for several decades, since the release of the first “vinyl” by Columbia in 1948, progress in this area has been directed not towards improving the media, but towards the design of playback devices that put as little pressure on the needle as possible.

Devices for reproducing information

A new analog format for recording sound or video always required a new device for playing it. If necessary, you have to look for this device, or even better, provide the ability to read old and new formats in one device. Advances in electronics have made this process simple for the manufacturer, but more complex for the user. A striking example is household video recorders. Traditionally, they support at least five interface standards: component, composite, S-Video, SCART and HDMI (and the long-outdated S-Video is found in several types of connectors). Computer video devices expand this variety to a complete immensity. In them you can find both analog VGA and various fashionable digital interfaces, among which there are the common DVI (of three varieties - DVI-A, DVI-I and DVI-D) and IEEE 1394, and the exotic DisplayPort, DVB, SDI and UDI.

Fortunately, many of these interfaces are compatible with each other at the adapter level. For example, you can turn digital DVI into digital HDMI, and analog VGA into analog S-Video. But, unfortunately, it is impossible to turn an analog interface into a digital one in such a simple way. Therefore, it is necessary to retain many interfaces in video devices, often no longer needed, but ensuring compatibility with all existing equipment, including ancient television receivers from the early 1980s.

The same difficulties can arise with computer digital data - over the past 20 years, not only floppy disks have become a thing of the past, but also streamers and magneto-optical disks (Iomega Zip, etc.), which have managed to spread among science and finance. In 2008, the US National Aeronautics and Space Administration (NASA) discussed plans for new lunar expeditions. Scientists needed data on the properties of lunar dust collected during the Apollo expeditions in the late 1960s. This information was recorded on 173 magnetic tapes, but their originals were lost at NASA. Fortunately, copies are preserved at the University of Sydney. However, to read them, a special magnetic tape drive was needed - the IBM 729 Mark V, produced in the 1950s and 1960s. It turned out that the once popular tapes (with a multi-track parallel data presentation format) were no longer readable. However, fortunately for the researchers, a suitable copy of the drive was found at the Australian Computer Museum.

A similar story happened to American archivists in the 1990s, when they set out to get acquainted with the 1960 census data stored on magnetic media. There were only two computers in the world capable of reading this data. One of them was in the USA, the other in Japan. Learned from this experience, the world's largest Library of Congress (USA) has created a special unit that stores devices for reading information from outdated electronic media. However, there is no certainty that somewhere in the archive there will not be found a medium in such an original format that no devices or software have been preserved to read it.

Digital media

Digital media, which replaced all these vinyl discs, films and tapes, also leaves much to be desired in terms of durability - many of them fail simply during storage. Even if you find a readable drive for 5-inch floppy disks, they will most likely not be readable - neither at all nor partially. True, not long ago I had to read a 5-inch Bulgarian-made Izot floppy disk, recorded on a Pravets-16 computer in the late 1980s. Imagine, the data on it turned out to be intact (it’s not for nothing computer components of the Soviet era passed military acceptance!), but in general you shouldn’t count on this. And 3-inch floppy disks, while more durable during use, are still less durable than 5-inch ones, since information is recorded on them at a higher density.

A hard drive (hard drive) has a service life of about five years, although manufacturers declare much longer. It often fails even faster - especially when it heats up during operation. And this state of his is more common than an exception. Back in 2007, researchers from Carnegie Mellon University examined approximately 100 thousand drives from different manufacturers and found that the main indicator of reliability - mean time before failure (MTBF) - was overestimated by manufacturers by approximately 15 times. According to their data, not 1% of disks fail every year, but 2–4%, with failure peaks observed in the first year of operation, as well as after the fifth to seventh year. The researchers did not name the manufacturers whose drives showed the highest failure rate. But it turned out that drives, both aimed at the mass market and those intended for the professional sector (and therefore more expensive), positioned not only as high-performance, but also as having increased reliability, actually demonstrate similar performance.

The most persistent of optical disks(CD and DVD) are considered stamped. They, as the manufacturers claim, are capable of operating without failure for more than 30 years when stored in good conditions. And recordable and especially rewritable CDs and DVDs can lose data already in the first decade of their existence. Moreover, due to the peculiarities of information presentation, audio compacts (Audio CDs) are more reliable than data disks containing a real file system.

We can assume that the durability of flash storage devices is the same as that of stamped optical disks. It should be noted that the reliability of storing information on flash drives increases significantly if it is periodically, at least once every few years, rewritten.

Data formats

As already noted, for analog video and audio media, the problem of data formats is finding the right equipment. Suffice it to remember that since the invention of the VCR in 1956, about 30 different incompatible formats have been used for video recording, forcing broadcasters and archives to store multiple devices “just in case.” For digital formats that exist as computer files (that is, for all but the classic Audio CD, where there are no files as such), reading obsolete or rare formats is easier. In addition, analog conversion and copying of data are always accompanied by information losses. And converting data from one digital format to another is a fully automated procedure, and this process, in principle, can proceed without losses. Losses may accompany conversions of compressed formats, but they are not as significant as when copying analog information, and their level is easily controlled.

The ease of reading and converting digital formats results in too many of them. For example, there are several dozen varieties of archivers, in addition to the well-known ZIP and RAR. Moreover, some of them, created with a specific application in mind, are not used outside a certain limited area. But if for older types of media you need a special reading device (perhaps like tape recorders or film, based on physical principles no longer used), then to read a file of the old format you only need the appropriate program. And if it is missing, then it is not difficult to find it, or, as a last resort, write it again, which will be cheaper than creating an entire playback device.

The larger the volume occupied by this type of information, the greater the variety of types of digital data observed for it. In practice, only a few text formats are used - “pure text”, a couple of Microsoft formats (DOC, DOCX and RTF), Open Document Format (ODF), as well as the HTML web format and also “illustrated text” PDF. The remaining types of text presentation relate mainly to various manufacturers of electronic readers, which have produced about one and a half dozen different formats adapted to specific devices. And therefore, in everyday life, problems with text formats now very rarely arise - they mainly concern the conversion of various language encodings.

Relatively few formats are used in practice to represent static images. Their list is practically limited to five varieties: TIFF, JPEG, GIF, BMP and PNG. The remaining existing formats are mainly tied to specific application areas or graphics programs. It should be noted that there are significantly more formats for sound than for text and images, and for video presentation the variety is even greater, especially among those used in practice. This is due to the fact that sound and video files take up much more space than text or static images, and in order to be presented in a volume acceptable for user purposes, they must be compressed using various methods. At the same time, compression methods differ depending on the purpose of encoding - on the Internet, video and sound must be presented as compactly as possible, even sacrificing quality. But for recording on DVD, and especially in Blu-Ray format, you can swing wider.

And therefore, it is not so rare that a video disc recorded on a household player refuses to play on a computer, or vice versa. In addition, it should be taken into account that common types of video files like AVI, OGG or MPEG-4 are not yet formats, but so-called “containers”. A container is a wrapper for the content itself, which can be presented in a variety of formats. Containers include not only video formats, but also many familiar types of text, sound files or images (say PDF, WAV or BMP - also containers). It is in the field of video production that the problem of format diversity is most acute. For example, the developers of the MPEG-4 standard left private developers a certain freedom in determining methods and techniques for video compression. Therefore, you should not be surprised that a video disc recorded on one computer will not “want” to be played on another, which does not have a codec program suitable for this format.

Archivists solve the format problem relatively easily and cheaply. Through trial and error, archivists in developed countries have developed a number of solutions, the main one being the storage of information in machine-independent, standardized forms. Naturally, the text format became the basic format - what in computer programs called "pure text". Digital tables are cleared of all additional data that accompanies them when created in specific programs like Excel, and are presented as a sequence of purely text characters.

However, the use of proprietary formats in archives is not excluded. At the input, all documentation is converted into a format that is optimal for storage, and at the output, when transferred to a specific user, the reverse procedure is performed - converting the data into the format most convenient for the user.

The conclusion is simple: digital data on modern media has a huge advantage over old analog ones - they are simply and quickly rewritten without loss, and the copy is identical to the original. Therefore, the durability of digital media is not so important, since timely rewriting of information allows it to be stored almost forever. Data should be stored digitally on modern media and changed when there is a danger of it becoming obsolete and disappearing from use. This also requires time and money, but much less than creating conditions for storing unique information recorded on analog media in previous centuries.

How to do all this so that it is both reliable and convenient?

What to do?

For reproducing obsolete storage media in everyday life, the solution used in the Library of Congress is practically unacceptable. No one will keep a huge reel-to-reel tape recorder or film projector just so that once every few years, when the mood strikes, they can listen to old recordings or watch family newsreels. The only way to get around this obstacle is to take the time and money, digitize the archives and store them on modern media in digital form. For government and other large archives, this is also the only way to preserve old originals presented in analogue formats. Moreover, conversion to “digital” makes information more accessible - it becomes possible to publish it, send it and copy it without risk to the original (remember that film and magnetic recordings degrade when copied, paper wears out and breaks, and paints on ancient paintings fade from exposure to light).

The amount of work ahead in this area is enormous, and only a small part of the old information has been digitized around the world. Note that a significant amount of information continues to be released in traditional form. For example, domestic book publishing produces approximately 50–60 thousand titles of book products per year in printed form, while the largest Russian-language electronic libraries (like the famous “Librusek”) contain no more than 100–200 thousand digitized books, i.e. output volume for two to three years. Consequently, a huge part of the information array in the near future, when the transition to electronic media takes place, will most likely remain inaccessible. By the way, the existing legislation on intellectual property does not make this task easier, but rather hinders its solution.

The world is gradually moving towards information without carriers. Many companies offer data storage in the cloud, i.e. in distributed storage without a specific location. But you should hardly trust such services completely. Storage managed from single center, is not much more reliable than storing copies locally on users’ computers, which is easy to show with examples.

On mass electronic mail services or on services such as Google Docs, there are constant failures that interrupt access. A global failure of such services with irretrievable loss of data is a hypothetical scenario, but not at all fantastic. In addition, the centralized storage can be disconnected from user access at any time, and this is already a political issue. By the way, the security issue in such storage facilities cannot be resolved in principle: any computer protection can be hacked.

And here’s another scenario from which no one is safe: I recently happened to irretrievably lose an archive of very valuable photographs taken at my request at a conference where many distinguished figures in the computer industry from Soviet times gathered in one place. A girl photographer's disk on which the photographs were stored crashed. At the same time, neither she nor I made copies, relying on Google’s Picasa photo hosting service. But by the time the breakdown was discovered, the gallery posted there was no longer accessible, because no one bothered to pay attention to the limited shelf life. The combination of circumstances, as you can see, is not at all unique.

From these examples it follows, in general, a simple, although rather cumbersome to implement, recipe for those who are concerned about the safety of their archives.

First you need to convert all analog originals into digital form. More often than not, this is easier said than done. Thus, digitization of photographs (including negatives with slides) is now offered on almost every corner, but with amateur films and tape recordings the situation is much more complicated and it is much more expensive to get out of it.

However, having solved this problem, it is worth remembering that digital form in itself does not guarantee safety. The durability of digital media is even less than that of traditional paper or film; they only allow you to make as many copies as you like without loss of quality without any extra cost or effort. This advantage of numbers is worth taking advantage of to the fullest.

Store valuable data in at least three copies. One working one, with which you manipulate every day, and another one for quickly restoring individual folders and files, and place it on a separate hard drive (or even on a separate computer). And finally, another copy should be stored as an image of an entire file partition for emergency recovery in case of major failures. It is convenient to store such a “backup” in a special file storage with a RAID array (known as NAS - Network Attached Storage). But if the Internet channel allows it, then, of course, it’s a good idea to upload the image somewhere to the cloud, you just need to ensure its safety and timely updating. Then you have a chance to recover your data even if all your devices are destroyed in a fire or other natural disaster.

Main types of storage media

Information carriers: living beings, inanimate objects and structures, signal, sign, symbol. Any object carries some information about itself and the objects around it, that is, it is a carrier of information.

There is an idea that information carriers have material, material and relational properties. The former imply the properties of the substances from which the carriers are made; the second are the properties of processes and fields with the help of which media exist, and the third are elemental (species) properties that make it possible to distinguish some media from others, for example, by shape and size. Physical media are divided into: local (computer), alienable (portable disks and floppy disks) and distributed (communication lines). Regarding the latter, there is no clear opinion because communication channels can be represented as data carriers, but at the same time they are the medium for their transmission.

Usually under information carriers imply the generally accepted name for their form, that is: paper (book, brochure, etc.), record (gramophone record, photographic plate), film (photo, film, x-ray film), audio cassette, floppy disk, microform (photographic film, microfilm, microfiche), video cassette, CD ( CD, DVD) etc.

Such media have long been known: stone (rock paintings, stone slabs), clay tablets, parchment, papyrus, birch bark and others. Then the following media appeared: paper, plastic, photographic materials, magnetic and optical materials, and more.

Nowadays they are divided into: traditional and machine-readable. Under traditional We will understand the following information media: paper, canvas, plastic (gramophone record), magnetic tape (audio and video cassette), photographic materials (photographic film, photographic plate, photographic print, micromedia), etc. TO machine readable media We include: floppy disks (floppy magnetic disks), hard magnetic and compact (optical, magneto-optical and other) disks, flash cards and other storage media intended for use in computer devices, complexes, systems and networks. Information is recorded on a medium by changing the physical, chemical or mechanical properties of the storage medium.

Option for classifying storage media used in computer technology, is shown in Fig. 5-1.

Rice. 5-1. Classification of storage media used

in computer technology

Note that this division is conditional. For example, using special devices on computers, you can work with ordinary audio and video cassettes, and devices for recording and long-term storage of data (streamers) use well-known magnetic media (magnetic tapes), etc. Therefore, we will refer to traditional media as analogue data, and as machine-readable, that is, used in computers, as digital or electronic data. information resources(EIR).

Let's give them a brief description.

Magneto-optical disk (MO) disk is enclosed in a plastic envelope (cartridge). MO-disk is a universal, fast, highly reliable device for transferring and storing information. Characterized by high density of information recording. Disks with a diameter of 3.5" have a capacity of 128 MB - 1.3 GB, and with a diameter of 5.25" - from 2.3 to 9.1 GB. Disk rotation speed – 2000 rpm.

Story

The need to exchange information, preserve written evidence about one’s life, etc. has always existed for humans. Throughout the history of mankind, many information carriers have been tried. Since the medium has a number of parameters, the evolution of the information medium was determined by what requirements were placed on it.

Ancient times

Ancient people depicted the animals they hunted on the rocks. However, coal, clay, and chalk drawings were washed away by rain, and to increase the reliability of storing information, primitive artists began to carve silhouettes of animals on the rocks with a sharp stone. Although the stone increased the security of information, its recording speed and transmission left much to be desired. Man began to use clay for writing, which had the properties of stone (preservation of information), and its plasticity and ease of writing made it possible to increase the efficiency of recording.

The ability to write effectively contributes to the emergence of writing. More than five thousand years ago (the achievement of the Sumerian civilization, the territory of modern Iraq) writing on clay appeared (no longer drawings, but icons and pictograms similar to letters). The Sumerians extruded signs on tablets made of raw clay with a reed stick sharpened by a “wedge” (hence the name - cuneiform) . Large documents consisting of dozens of clay “pages” were stored in boxes (“folders”).

Clay was difficult for large texts, the need for which was increasing. Therefore, another carrier had to appear to replace it

Egypt: papyrus

At the beginning of the third millennium BC. e. In Egypt, a new medium appears that has some improved parameters compared to clay tablets. There they learned how to make almost real paper from papyrus (a tall herbaceous plant). From the word “papyrus” comes the name of paper in some languages: French. papier- in French and German, English. paper- in English, Spanish papel- in Spanish, Belor. paper- in Belarusian. A bunch of papyrus leaves looks like the rays of the sun (the god Ra), the cut of the triangular stem has the shape of a pyramid, so the plant was considered royal.

The disadvantage of this medium was that over time it darkened and broke. An additional disadvantage was that the Egyptians introduced a ban on the export of papyrus abroad.

Asia

The disadvantages of storage media (clay, papyrus, wax) stimulated the search for new media. This time the principle “everything new is well-forgotten old” worked: in Persia, from ancient times, defter was used for writing - dried animal skins (in Turkish and related languages, the word “defter” still means a notebook), which the Greeks remembered.

Residents of the Greek city of Pergamon (the first to adopt ancient technology) improved the process of tanning hides and in the 2nd century BC. e. began the production of parchment. The advantages of the new medium are high reliability of information storage (strength, durability, does not darken, does not dry out, does not crack, does not break), reusability (for example, in a surviving prayer book of the 10th century, scientists discovered several layers of notes made lengthwise and crosswise, erased and erased, and with the help of x-rays, the ancient treatise of Archimedes was discovered there). Books on parchment are palimpsests (from the Greek παλίμψηστον - a manuscript written on parchment using washed or scraped text).

As in other countries, Southeast Asia has tried many different ways recording and saving information:

• burning on narrow bamboo plates with fastening with cords into “bamboo books” (disadvantage - they take up a lot of space, low wear resistance of the cords);
• letter to:
• silk (disadvantage is the high cost of silk),
• palm leaves sewn into a “book” (the paper sheet of a modern book is called so in memory of its palm prototype).

Due to the shortcomings of the previous carriers, the Chinese emperor Liu Zhao ordered a worthy replacement to be found, and one of the officials (Cai Lun) in 105 AD. e. developed a method for producing paper (which has not changed much to this day) from wood fibers, straw, grass, moss, rags, tow, plant waste, etc. Some historians claim that Tsai Lun learned the process of making paper from the paper wasp ( builds a nest from wood fibers chewed by it and moistened with sticky saliva). However, evidence has now been found in favor of the fact that paper began to be made even earlier.

Europe

On the territory of Europe, highly developed peoples (Greeks and Romans) groped for their own recording methods. Many different media are used: lead sheets, bone plates, etc.

Since the 7th century BC. e. recording is made with a sharp stick - a stylus (as in clay) on wooden tablets covered with a layer of pliable wax (so-called wax tablets). Erasing information (another advantage of this medium) was done with the opposite blunt end of the stylus. Such boards were fastened in groups of four (hence the word “notebook”, since the ancient Greek τετράς translated from Greek means four).

However, inscriptions on wax are short-lived, and the problem of preserving records was very pressing.

America

In the 11th-16th centuries, the indigenous peoples of South America came up with the knotted letter “quipu” (quipu translated from the language of the Quechua Indians - knot). “Messages” were made from ropes (rows of laces were tied to them). The type, number of knots, color and number of threads, their arrangement and weave constituted a “coding” (“alphabet”) of the quipu.
The Indian tribes of North America encoded their messages with small shells strung on cords. This type of writing was called "wampum" - from the Indian word wampam (short for wampumpeag) - white beads. The interweaving of cords formed a strip, which was usually worn as a belt. Entire messages could be composed by combining colored shells and drawings on them.

Ancient Rus'

Birch bark (the top layer of birch bark) was used as a carrier. The letters were cut out with a writing tool (a bone or metal stick).
By the end of the 16th century, Rus' had its own paper (the word “paper” most likely came into Russian from Italian, bambagia - cotton).

Types of storage media: (if asked!!!)

• Hard magnetic disk, LMD, HDD (hard disk, HD). It is used as the main stationary storage medium in computers. Large capacity, high access speed. Sometimes there are models with a removable disk that can be removed from the computer and hidden in a safe. This is what the HDD looks like.
• Flexible magnetic disk, floppy disk (FD) or floppy disk (diskette). Main removable media for personal computers. Small capacity, low access speed, but the cost is also low. The main advantage is transportability.
• Laser compact disc (CD, CD-ROM). Large capacity average speed access, but there is no ability to record information. The recording is made on special equipment. This is what a CD drive looks like.
• Rewritable laser compact disc (CD-R, CD-RW). In some cases, only recording is possible (without rewriting); in others, there is also a limited number of data rewriting cycles. Same characteristics as a regular CD.
• DVD. Similar to CD-ROM, but has a higher recording density (5-20 times). There are devices for both reading and writing (rewriting) DVDs.
• Replaceable magnetic disk type ZIP or JAZZ. Similar to a floppy disk, but has a much larger capacity. This is what the ZIP disk and drive for it look like.
• Magneto-optical or so-called floptic disk. High capacity removable media. This is what a magneto-optical disk and drive for it look like.
• A magnetic tape cassette is a removable medium for a streamer, a device specifically designed for storing large amounts of data. Some computer models are adapted to record information on ordinary tape cassettes. The cassette has a large capacity and high read-write speed, but slow access to an arbitrary point on the tape. This is what the streamer and its cassettes look like.
• Punch cards are almost never used nowadays.
• Punched paper tape is currently almost never used.
• Cassettes and ROM chips (read-only memory, ROM). They are characterized by the impossibility or difficulty of rewriting, small capacity, relatively high access speed, as well as high resistance to external influences. Commonly used in computers and other electronic devices for specialized purposes, such as game consoles, control modules of various devices, printers, etc.
• Magnetic cards (strips). Small capacity, transportable, the ability to combine machine-readable and plain text information. Credit cards, passes, identification, etc.
• There are a large number of specialized media used in various less common devices. For example, magnetic wire, hologram.

The beginning of beginnings (evolution of storage media)
XVIII century, France, city of Lieu. Textile master Basil Bouchon developed an elegant way to control the machine. He was the first to install a roll of paper with holes made in the right places into a drum, after which the machine was able to reproduce a given pattern on the fabric. The invention made it possible to create very intricate weavings automatically.

Here we need to make a lyrical digression. Monsieur Bouchon was the son of an organ collector, these musical instruments work on a similar principle. Watching his father work, the young man came up with a technology that later turned the world upside down. Bouchon was the first to find a way to store commands on a separate medium that could be replaced and reused.

Time passed, the invention was further developed. First, Jean-Baptiste Falcon suggested using rectangular sections connected together instead of a roll of paper, then Jacques Vacanson improved the Bouchon-Falcon machine and made it automatic - human participation became unnecessary. By the way, the world's first robots (a robot flute player and a duck) belong to the hands of a resourceful inventor. Unfortunately, they were lost...

Worldwide success and fame came to the textile machine in 1801, when Joseph Marie Jacquard refined the technology once again. Why do we spend so much time talking about textile machines? The fact is that the Jacquard machine went down in history as the prototype of a computer. The mechanical design, of course, could not carry out calculations, but changing operating modes using punched cards formed the basis of programming technologies. In the context of our research, what is primarily interesting is the method of storing commands on a medium - paper (in the form of a punched card).

The next stop of our time machine is the 30s of the 19th century. The legendary mathematician, analytical philosopher and engineer Charles Babbage lived at this time. He is known as the first computer system architect. In 1822, he began assembling a difference machine (automation of calculations). According to Babbage's plan, the machine had to calculate the values ​​of polynomials (polynomials) - this process took a lot of time and led to a large number errors. Unfortunately, technical difficulties did not allow us to finish what we started.

Another of Babbage's projects, the Analytical Engine, would use punched cards to load a program. The inventor proposed a concept unheard of at that time: the program was compiled on a paper punched card, installed in a machine, and it executed further actions. By the way, Ada Lovelace, who went down in history as the first programmer (in the 1970s, a programming language was named after her), helped create programs on punched cards. The ingenious idea could not be realized technically; only at the beginning of the 20th century did followers assemble an analytical engine based on Babbage’s drawings.

The subsequent fate of the data carriers is closely connected with the activities of Herman Cholerite. The next census was scheduled for 1890 in the United States. Organizing the results of the previous census took seven years. The government decided to optimize the process and try the method proposed by Cholerite. Herman assembled a mechanism for reading and processing data recorded on a punched card. Using the new approach made it possible to complete the census in just 2.5 years.

Cholerite subsequently founded the Tabulating Machine Company and went into sales. The business turned out to be profitable; in 1911, three more companies joined Herman to form the Computing Tabulating Recording Corporation, later renamed IBM.

By 1937, 32 machines at the IBM plant in New York were printing 5-10 million punched cards every day. Paper media were used everywhere and received the status of official documents. It is quite possible that punch cards would have gone down in history earlier, but the world was overwhelmed by the Second World War.

The era of magnetic tape

At this time, the German engineer Fritz Pflumer created magnetic film. The new carrier consisted of a thin layer of paper coated with iron oxide powder. Pflumer sold the technology to AEG, which developed the world's first recording and playback device, the Magnetophon. The invention was carefully hidden until Germany surrendered. Only in the early 1950s did magnetic film break out of the country.

The innovation was picked up by record and television companies, which began to use film to record audio and video. Technology entered the world of computers in 1951, when Eckert-Mauchly released the UNIVAC I system. The first thing the computer got into was the very bureau where the history of IBM began - the Census Bureau. The magnetic film used in UNIVAC stored much more information compared to paper punched cards (10,000 punched cards = 1 reel of film). IBM did not stand aside and switched to a new type of media. To translate the backlog of punch cards, Eckert-Mauchly and IBM introduced automatic converters.

Over time, reels of film were wrapped in plastic boxes, and it is in this form that “cassettes” have survived to this day. Film has become the de facto standard for recording data, video and music.

The year 1967 came, IBM management instructed one of the engineers to develop a fast and compact medium to send software updates to customers. David Noble's team has developed a flexible 8-inch (20 cm) disk with a capacity of 80 KB with the ability to write once. The product was fragile and attracted a lot of dust. The modified version was packaged in fabric, sealed in plastic and called FD23. The development was called “floppy” or “floppy disk” (the plastic packaging was thin and flexible, the carrier seemed to “flap its wings” when it was carried in the hands or shook in the air - hence the name floppy, from English word flop - clap). Computers began to be equipped with floppy drives for reading floppy disks, but the path to success was not easy. The disk drive cost the same as the computer itself, and many continued to use film cassettes.

In 1972, Alan Shugart left IBM and moved to Memorex. There, an engineer developed the Memorex 650, a rewritable floppy disk with a capacity of 175 KB. 8-inch floppy disks were further developed, bringing the volume to 1000 KB.

However, 8 inches is a bit much for mobile media. One day, two employees from Shugart Associates (founded by Alan Shugart) were sitting at a bar with An Wang from Wang Laboratories and discussing the appropriate size for a floppy disk. Then the idea was born that a floppy disk should not be larger in size than a napkin (5.25 inches or 13 cm). The first samples of 5.25-inch floppy disks could hold up to 98 KB of data. It was the first format that was not promoted by IBM. Over time, the size of the floppy disk increased to 1200 KB.

Optical technology is winning

In 1979, Philips and Sony joined forces to create a revolutionary media based on optical technology. Research began back in 1977 by Philips engineers, and the first compact disc (CD) was born in 1982.

The recording method was based on the concept of heating the surface of the disk and forming dots on it at strictly defined intervals. Changing a point to a flat surface means one, no change means zero. There are different legends about the size of the disk. They say that the 120 mm diameter was not chosen by chance - a disc of this size can accommodate exactly 74 minutes of audio with 16-bit encoding and 44.1 kHz quality. Well, 74 minutes is the duration of the 9th symphony by Ludwig van Beethoven...

On August 17, the Philips plant released an album by the Swedish group ABBA on CD, and players also appeared on the market at the same time. By 1985, many record companies had switched to CDs, and record player prices were falling. Of course, because the compact and lightweight disc, weighing only 16 g, had a thickness of 1.2 mm, while containing 74-90 minutes of high-quality sound.

It became clear that CDs can also be used to record data. In 1985, Sony and Philips developed the CD-ROM (Compact Disk Read Only Memory) standard, which allows data to be written to disk. Only manufacturers in factories could burn CDs. Despite the advantages of CDs, floppy disks remained popular.

The limitations and disadvantages of 5.25-inch floppy disks are obvious - the media is quite large and fragile, and dirt can easily penetrate into the cracks. Several companies have taken up the challenge of developing new standards. As a result, a variety of modifications appeared that were incompatible with each other. Sony solved the problem by introducing a relatively simple design 3.5-inch floppy disk with a retractable shutter. Several companies, including Apple, supported Sony's development. Over time, the size of floppy disks increased from 400 KB to 1.44 MB.

In 1991, Insite Peripherals entered the scene with Floptical. Engineers combined a standard floppy drive with an infrared diode to position the read head, which made it possible to increase the floppy disk capacity to 21 MB. At the same time, the drive could read regular floppy disks. The only drawback of Floptical is the connection via an expensive SCSI interface. Three years later, Iomega introduced Zip. Despite the similar format and dimensions of 3.5 inches, the new drives could not read regular floppy disks. Iomega introduced floppy disks with capacities of 100, 250 and even 750 MB, but technical problems and the high cost of media have done their job, no one remembers Zip anymore.

CDs became more popular than ever in the mid-1990s, when special formats for recording video (Video CD, Super Video CD) and photos (Photo CD, Picture CD) appeared. In the early 90s, Sony and Philips introduced CD-R (Compact Disk Recordable) - CDs with the ability to write once. The next starting point was 1998, when the same couple Sony and Philips developed a rewritable CD-RW (Compact-Disk Rewritable) disc. At the same time, the DVD format loomed on the horizon...

Laser disc

The first optical storage medium was the so-called Laserdisk (LD), demonstrated by Philips and MCA in 1972. They tried to push a huge 30-centimeter disk as a replacement for VHS video cassettes. Laserdisk was an almost entirely analogue medium with digital audio; the discs could hold up to 60 minutes of video. Typically, producers released films on dual media.

Initially, the disc had to be turned over after 60 minutes to the other side. Then equipment manufacturers released players in which the reading head learned to move from one side to the other, while the viewer still had to wait for the reading to begin. Films on two or more discs are a different story. Especially for such kits, Pioneer released a player with two trays.

The technology was renamed several times, but it was never saved. Players with LD support appeared until 2003. Nowadays it is a rarity.

Instead of an epilogue

Everyone knows what happened next - recordable and rewritable DVDs, large flash drives, etc. appeared. Around 2000, the last stronghold of the era of magnetic films - video cassettes - finally went into history. Now in the data storage market there are fierce wars between HD-DVD and Blu-ray, new generation technologies. And in the future we can expect holographic disks with a capacity of 300 GB per disc...

) are used for:

• records
• storage
• reading
• transmission (distribution)
• creating works of computer art

In general, the boundaries between these types of media are quite vague and may vary depending on the situation and external conditions. Basic materials paper (punched tape, punched card, sheets); plastic (bar code, optical discs); magnetic materials (magnetic tapes and disks); Also previously widespread were: baked clay, stone, bone, wood, parchment, birch bark, papyrus, wax, fabric, etc. To make changes in the structure of the carrier material, various types of influence are used: thermal (burning); Electronic media Electronic media include media for single or multiple recording (usually digital) electrically: CD-ROM, DVD-ROM, semiconductor (flash memory, etc.), floppy disks. They have a significant advantage over paper (sheets, newspapers, magazines) in terms of volume and unit cost. For storing and providing operational (not long-term storage) information, they have an overwhelming advantage; there are also significant opportunities for providing information in a form convenient for the consumer (formatting, sorting). Disadvantage - small screen size (or significant weight) and fragility of reading devices, dependence on. Currently, electronic media are actively replacing paper media in all sectors of life, which leads to significant wood savings. Their disadvantage is that to read AND for each type and format of media, you need a corresponding reading device. Storage devices The disadvantage of this medium was that over time it darkened and broke. An additional disadvantage was that the Egyptians introduced a ban on the export of papyrus abroad. Asia The disadvantages of storage media (clay, papyrus, wax) stimulated the search for new media. This time the principle “everything new is well-forgotten old” worked: in Persia, from ancient times, defter was used for writing - dried animal skins (in Turkish and related languages, the word “defter” still means a notebook), which the Greeks remembered. Europe On the territory of Europe, highly developed peoples (Greeks and Romans) groped for their own recording methods. Many different media are used: lead sheets, bone plates, etc. Since the 7th century BC. e. recording is made with a sharp stick - a stylus (as in clay) on wooden tablets covered with a layer of pliable wax (so-called wax tablets). Erasing information (another advantage of this medium) was done with the opposite blunt end of the stylus. Such boards were fastened together in groups of four (hence the word “notebook”, since ancient Greek. τετράς translated from Greek - four). However, inscriptions on wax are short-lived, and the problem of preserving records was very pressing. America In the 11th-16th centuries, the indigenous peoples of South America came up with the knotted letter “quipu” (quipu translated from the language of the Quechua Indians - knot). “Messages” were made from ropes (rows of laces were tied to them). The type, number of knots, color and number of threads, their arrangement and weave constituted a “coding” (“alphabet”) of the quipu. The Indian tribes of North America encoded their messages with small shells strung on cords. This type of writing was called "wampum" - from the Indian word wampam (short for wampumpeag) - white beads. The interweaving of cords formed a strip, which was usually worn as a belt. Entire messages could be composed by combining colored shells and drawings on them. Ancient Rus' Birch bark (the top layer of birch bark) was used as a carrier. The letters on it were cut out with a writing tool (a bone or metal stick). By the end of the 16th century, Rus' had its own paper (the word “paper” most likely came into Russian from Italian, bambagia - cotton). Middle Ages In the ancient world and the Middle Ages, wax tablets were used as notebooks, for household notes and for teaching children to write. New time Modernity Nowadays people use computers to process and store information. See also Bearer of the name Bearer of the surname Nucleic acids (DNA, RNA) Links Notes Wikimedia Foundation. 2010. See what “Information carrier” is in other dictionaries: Storage medium- an individual or a material object, including a physical field in which information is reflected in the form of symbols, images, signals, technical solutions and processes, quantitative characteristics of physical quantities. Source … Dictionary-reference book of terms of normative and technical documentation INFORMATION CARRIER- (recording medium) an intermediate link between a computer (device) and primary (see), registered in a formalized form by changing the physical, chemical. or mechanical properties of the storage medium or physical. bodies and used for recording,... ... Big Polytechnic Encyclopedia Any material object or medium used to store or transmit information Dictionary of business terms. Akademik.ru. 2001 ... Dictionary of business terms carrier (of information)- carrier (frequency) - Topics information security Synonyms carrier (frequency) EN carrier ... Storage medium- according to GOST 7.0 99, means of recording, storing, transmitting information, or otherwise, material on which information can be recorded. Types of N. and.: 1) human-readable (human-readable), used to record data directly readable... ... Publishing dictionary-reference book An individual or material object, including a physical field, in which information is displayed in the form of symbols, images, signals, technical solutions and processes. Political science: Dictionary reference book. comp. Prof. Paul Sciences... ... Political science. Dictionary. storage medium- - [Ya.N.Luginsky, M.S.Fezi Zhilinskaya, Yu.S.Kabirov. English-Russian dictionary of electrical engineering and power engineering, Moscow, 1999] Topics of electrical engineering, basic concepts EN data carrierrecord mediumrecording medium ... Technical Translator's Guide storage medium- Rus: information carrier [data] Eng: information carrier Fra: milieu de l information Means of registration, storage, transmission of information (data). GOST 7.0... Dictionary of Information, Librarianship and Publishing Machine, recording medium, body, substance used for recording and storing information for the purpose of directly entering it into a computer. N. and. is an intermediate link between the machine and primary documents containing numerical data... ... Great Soviet Encyclopedia Read more

Storage medium (data medium) - a material object or environment intended for storing data. Recently, storage media are mainly called devices for storing data files in computer systems, distinguishing them from devices for input/output of information and devices for information processing.

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

Capacity digital media means the amount of information that can be written to it, it is measured in special units - bytes, as well as in 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).