A slang word very often used in circulation - flash drive, has become so firmly established in everyday life that many have forgotten how to correctly call this device, while others do not even know.

This miniature device is used to copy, save and transmit digitized information. Correct device name:

USB indicates a way to connect a flash drive to other devices through special ports, and flush reports that the functions of storing and copying information have been implemented using non-volatile flash memory on semiconductors.

The advantages of flash drives are their small size, quiet operation and shock resistance.

Electronics sellers in stores also use the name flash drive.

Officially, a flash drive is called a USB flash drive, since it is a storage device that uses flash memory as a medium and is connected to a computer or reading device via USB.

• USB flash drive

  This is what Wikipedia officially calls a flash drive.

  By the way, I would use the word flash drive and USB flash drive I recommended writing it with the letter e. The same Wikipedia gives the following official English name for this device: USB flash drive. In this case, we are interested in the word flash. This is where the word flash drive comes from. IN English There is also the word flesh, which has nothing to do with a flash drive.

The word flash drive is an abbreviated name for a flash card. You can also come across the names memory card and USB flash drive - this is a carrier of information converted into flash memory (you can read more about flash memory here), so the main characteristic of a flash card is its memory capacity.

The word flash drive is very widely used in everyday life; most people do not even know the correct name of this device. The full name:

The word flash means that information is stored from using Flash memory, USB connection to a computer.

A flash drive is officially considered a USB flash drive, which is capable of storing information copied into it and provides the ability to repeatedly transfer data from it to other electronic devices.

A flash drive is correctly called a USB flash drive. It's called USB because it plugs into this port on the computer. It’s called a drive because you can store information on it and conveniently carry a large amount of it with you. You must handle it carefully and stop working with it before removing it from the connector.

What is the correct name? flash drive, which has become so familiar to everyone - in fact, few people think about it. Other names that are used quite often are memory card or USB memory stick, flash (or flash) card or flash/flash drive.

In this case, the correct name of the flash drive is:

a device with removable media or flash memory or just a memory card

Well, for us it’s customary to call it a flash drive, it is a flash drive, they just call it correctly USB flash drive, and USB stands for this Universal serial bus, also called briefly flash, flash drive, flash drive

The flash drive is called flash card or flash memory card. Although in online stores this device called USB flash drive, so this is probably more correct.

There is also just a memory card, but this is somewhat different, those memory cards are used for mobile phones, although the principle of storing information seems to be the same for them: a flash method of memorization. Now they are also making BIOS on nm.

Flash memory is a type of long-lasting memory for computers in which the contents can be reprogrammed or electrically erased. Compared to Electrically Erasable Programmable Read Only Memory, operations on it can be performed in blocks that are located in different places. Flash memory costs much less than EEPROM, which is why it has become the dominant technology. Particularly in situations where stable and long-term data storage is required. Its use is allowed in a wide variety of cases: in digital audio players, photo and video cameras, mobile phones and smartphones, where there are special Android applications for the memory card. In addition, it is also used in USB flash drives, traditionally used to save information and transfer it between computers. It has gained some fame in the world of gamers, where it is often used to store game progress data.

General description

Flash memory is a type that is capable of storing information on its board for a long time without using power. In addition, we can note the highest data access speed, as well as better resistance to kinetic shock in comparison with hard drives. It is thanks to these characteristics that it has become so popular for devices powered by batteries and rechargeable batteries. Another undeniable advantage is that when flash memory is compressed into a solid card, it is almost impossible to destroy it by any standard physical means, so it can withstand boiling water and high pressure.

Low-level data access

The way to access data residing in flash memory is very different from that of conventional types. Low-level access is provided through the driver. Conventional RAM immediately responds to calls to read and write information, returning the results of such operations, but the design of flash memory is such that it takes time to think about it.

Design and principle of operation

At the moment, flash memory is widespread, which is created on single-transistor elements with a “floating” gate. This makes it possible to provide greater data storage density compared to dynamic RAM, which requires a pair of transistors and a capacitor element. At the moment, the market is replete with various technologies for constructing basic elements for this type of media, which are developed by leading manufacturers. They are distinguished by the number of layers, methods of recording and erasing information, as well as the organization of the structure, which is usually indicated in the name.

Currently, there are a couple of types of chips that are most common: NOR and NAND. In both, the storage transistors are connected to the bit buses - in parallel and in series, respectively. The first type has fairly large cell sizes and allows for fast random access, allowing programs to be executed directly from memory. The second is characterized by smaller cell sizes, as well as fast sequential access, which is much more convenient when it is necessary to build block-type devices where large amounts of information will be stored.

In most portable devices, the SSD uses the NOR memory type. However, devices with a USB interface are becoming increasingly popular. They use NAND memory. Gradually it displaces the first one.

The main problem is fragility

The first samples of mass-produced flash drives did not please users with high speeds. However, now the speed of writing and reading information is at such a level that you can watch a full-length movie or run an operating system on your computer. A number of manufacturers have already demonstrated machines where the hard drive is replaced by flash memory. But this technology has very significant drawback, which becomes an obstacle to replacing existing magnetic disks with this medium. Due to the design of flash memory, it allows erasing and writing of information in a limited number of cycles, which is achievable even for small and portable devices, not to mention how often this is done on computers. If you use this type of media as a solid state drive on a PC, then a critical situation will come very quickly.

This is due to the fact that such a drive is built on the property field effect transistors store in a “floating” gate the absence or presence of which in the transistor is considered as a logical one or zero in binary. Writing and erasing data in NAND memory is carried out using tunneled electrons using the Fowler-Nordheim method with the participation of a dielectric. This does not require what allows you to make cells of minimal sizes. But it is this process that leads to the cells, since the electric current in this case forces electrons to penetrate the gate, overcoming the dielectric barrier. However, the guaranteed shelf life of such memory is ten years. Wear of the microcircuit occurs not due to reading information, but due to operations to erase and write it, since reading does not require changing the structure of the cells, but only passes an electric current.

Naturally, memory manufacturers are actively working towards increasing the service life of solid-state drives of this type: they are striving to ensure uniformity of writing/erasing processes across the cells of the array, so that some do not wear out more than others. To distribute the load evenly, software paths are predominantly used. For example, to eliminate this phenomenon, “wear leveling” technology is used. In this case, data that is often subject to changes is moved to the address space of flash memory, so recording is carried out at different physical addresses. Each controller is equipped with its own alignment algorithm, so it is very difficult to compare the effectiveness of certain models, since implementation details are not disclosed. Since the volume of flash drives is becoming larger every year, it is necessary to use more and more efficient operating algorithms to guarantee the stable functioning of the devices.

Troubleshooting

One of the very effective ways to combat this phenomenon is to reserve a certain amount of memory, which ensures load uniformity and error correction through special logical redirection algorithms for replacing physical blocks that arise during intensive work with a flash drive. And to prevent the loss of information, cells that fail are blocked or replaced with backup ones. This software distribution of blocks makes it possible to ensure load uniformity, increasing the number of cycles by 3-5 times, but this is not enough.

And other types of similar drives are characterized by the fact that a table with a file system is entered into their service area. It prevents failures in reading information at the logical level, for example, in the event of an incorrect shutdown or a sudden interruption in the supply of electrical energy. And since the system does not provide caching when using removable devices, frequent rewriting has the most detrimental effect on the file allocation table and directory table of contents. And even special programs for memory cards are not able to help in this situation. For example, during a one-time request, the user overwrote a thousand files. And, it would seem, I only used the blocks where they were located for recording once. But service areas were rewritten with each update of any file, that is, the allocation tables went through this procedure a thousand times. For this reason, the blocks occupied by this data will fail first. Wear leveling technology also works with such blocks, but its effectiveness is very limited. And it doesn’t matter what kind of computer you use, the flash drive will fail exactly when the creator intended it to.

It is worth noting that the increase in the capacity of the microcircuits of such devices has only led to the fact that the total number of write cycles has decreased, since the cells are becoming smaller, so less and less voltage is required to dissipate the oxide partitions that isolate the “floating gate”. And here the situation is such that with the increase in the capacity of the devices used, the problem of their reliability began to worsen more and more, and the class of the memory card now depends on many factors. The reliability of such a solution is determined by its technical features, as well as the current market situation. Due to fierce competition, manufacturers are forced to reduce production costs by any means. Including due to simplified design, the use of components from a cheaper set, weakening control over production and other methods. For example, a Samsung memory card will cost more than its lesser-known analogues, but its reliability raises much fewer questions. But even here it is difficult to talk about complete absence problems, and it’s hard to expect anything more from devices from completely unknown manufacturers.

Development prospects

While there are obvious advantages, there are a number of disadvantages that characterize the SD memory card, which prevent further expansion of its scope. That is why there is a constant search for alternative solutions in this area. Of course, first of all, they are trying to improve existing types of flash memory, which will not lead to any fundamental changes in the existing production process. Therefore, there is no doubt about only one thing: companies engaged in the manufacture of these types of drives will try to use their full potential before switching to another type, continuing to improve traditional technology. For example, the Sony memory card is currently available in a wide range of volumes, so it is assumed that it will continue to be actively sold out.

However, today, on the threshold of industrial implementation, there is a whole range of technologies for alternative data storage, some of which can be implemented immediately upon the onset of a favorable market situation.

Ferroelectric RAM (FRAM)

The technology of the ferroelectric principle of information storage (Ferroelectric RAM, FRAM) is proposed to increase the potential of non-volatile memory. It is generally accepted that the mechanism of operation of existing technologies, which consists in rewriting data during the reading process with all modifications of the basic components, leads to a certain limitation in the speed potential of devices. And FRAM is a memory characterized by simplicity, high reliability and speed in operation. These properties are now characteristic of DRAM - non-volatile RAM existing at the moment. But here we will also add the possibility of long-term data storage, which is characterized by: Among the advantages of such technology we can highlight resistance to different types penetrating radiation, which may be in demand in special devices that are used to work in conditions of increased radioactivity or in space research. The information storage mechanism here is implemented through the use of the ferroelectric effect. It implies that the material is able to maintain polarization in the absence of an external electric field. Each FRAM memory cell is formed by sandwiching an ultra-thin film of ferroelectric material in the form of crystals between a pair of flat metal electrodes, forming a capacitor. The data in this case is stored inside the crystal structure. And this prevents the effect of charge leakage, which causes the loss of information. Data in FRAM memory is retained even when the power supply is turned off.

Magnetic RAM (MRAM)

Another type of memory that is considered very promising today is MRAM. It is characterized by fairly high speed performance and energy independence. in this case, a thin magnetic film placed on a silicon substrate is used. MRAM is static memory. It does not need periodic rewriting, and information will not be lost when the power is turned off. At the moment, most experts agree that this type of memory can be called a next-generation technology, since the existing prototype demonstrates fairly high speed performance. Another advantage of this solution is the low cost of the chips. Flash memory is manufactured using a specialized CMOS process. And MRAM chips can be produced using a standard manufacturing process. Moreover, the materials can be those used in conventional magnetic media. It is much cheaper to produce large quantities of such microcircuits than all the others. An important property of MRAM memory is its ability to turn on instantly. And this is especially valuable for mobile devices. Indeed, in this type, the value of the cell is determined by the magnetic charge, and not by the electric charge, as in traditional flash memory.

Ovonic Unified Memory (OUM)

Another type of memory that many companies are actively working on is a solid-state drive based on amorphous semiconductors. It is based on phase transition technology, which is similar to the principle of recording on regular disks. Here the phase state of a substance in an electric field changes from crystalline to amorphous. And this change persists even in the absence of tension. Such devices differ from traditional optical disks in that heating occurs due to the action of electric current and not a laser. Reading in this case is carried out due to the difference in the reflectivity of the substance in different states, which is perceived by the disk drive sensor. Theoretically, such a solution has a high data storage density and maximum reliability, as well as increased performance. The maximum number of rewrite cycles is high here, for which a computer is used; a flash drive in this case lags behind by several orders of magnitude.

Chalcogenide RAM (CRAM) and Phase Change Memory (PRAM)

This technology is also based on the principle that in one phase the substance used in the carrier acts as a non-conducting amorphous material, and in the second it serves as a crystalline conductor. The transition of a memory cell from one state to another is carried out due to electric fields and heating. Such chips are characterized by resistance to ionizing radiation.

Information-Multilayered Imprinted CArd (Info-MICA)

The operation of devices built on the basis of this technology is carried out according to the principle of thin-film holography. Information is recorded as follows: first, a two-dimensional image is formed and transferred to a hologram using CGH technology. Data is read by fixing the laser beam on the edge of one of the recorded layers, which serve as optical waveguides. The light propagates along an axis that is parallel to the plane of the layer, forming an output image corresponding to the information recorded earlier. The initial data can be obtained at any time thanks to the reverse coding algorithm.

This type of memory compares favorably with semiconductor memory due to the fact that it provides high recording density, low power consumption, as well as low cost of storage media, environmental safety and protection from unauthorized use. But such a memory card does not allow rewriting of information, so it can only serve as long-term storage, a replacement for paper media, or an alternative to optical disks for distributing multimedia content.

information

A storage medium using flash memory (English Flash - “fast, instantaneous”) is a microcircuit with an electronic non-volatile memory capable of storing recorded information for an unlimited time and maintaining its state until an electrical signal of a different polarity is applied to the outputs. These are high-quality universal rewritable storage media, aimed at consumer electronics products and new generation computer equipment.

The following types of flash memory are available: CompactFlash, SmartMedia, Memory Stick, Floppy Disks, MultiMedia Cards, etc.

MultiMedia cards, for example, weigh less than two grams, the size of a postage stamp, with a memory capacity of 8 to 64 MB. Such cards can replace not only floppy disks, but magneto-optical disks, small hard disks and rewritable CDs. Modern flash cards have a capacity that is a multiple of two to the power: 26 = 64, 27 = 128, 256 = 28 MB, and so on. It is assumed that the maximum capacity of such cards will reach several GB. Such removable cards are used in digital voice recorders, portable players, video cameras, car radios, personal digital assistants (PDAs), cell phones and multimedia projectors.

Information carriers distinguish by physical structure(magnetic, semiconductor, dielectric, etc.), type of material(paper, plastic, metal, combined), data presentation form(printed, handwritten, magnetic, perforated), data reading principle(mechanical, optical, magnetic, electrical), design(tape, disk, card).Information media can also be classified by the type of messages stored on them, and the materials of information media are characterized by the purpose of their use.

By intended use Data storage media materials can be classified as materials used for recording, representing and storing text, digital, graphic data, static and dynamic images, sound (magnetic and non-magnetic) or a combination of these, for example, multimedia data. Both classifications are closely interrelated; moreover, it is impossible to unambiguously classify carrier materials. The types of different messages are presented in Table 5-1.

Table 5-1

Types of different messages

Message type	Storage medium
Text	Document
Sound	Phonogram
Image (static)	Photograph, graphic, drawing, etc., transparencies (slide), hologram, PC scanned static pictorial or text information
Image (dynamic)	Animation, video, film, TV
Combination various types information	Multimedia

As static carriers images used: paintings, etchings, drawings, etc. on canvas, cardboard, paper, film, etc.; video cassettes with magnetic tapes for VCRs and video players; magnetic vinyl floppy disks; removable and non-removable hard and magneto-optical disks; compact plastic or glass laser discs ( CD, DVD ), used in computers; slides and transparencies, photographic materials, holographic plates, memory plates for digital cameras such as flash memory, etc.

For the operation of audio-video equipment as sound carriers and/or dynamic images used: films and plastic gramophone records, magnetic audio and audiovisual tapes, film films, vinyl floppy disks, hard magnetic and magneto-optical disk drives, compact discs, memory plates for digital cinema cameras and cameras, holographic plates, etc.).

Multimedia data carriers Magnetic audio and audiovisual tapes, floppy disks, hard magnetic and magneto-optical disk drives, CDs, and memory platters are considered.

Information carriers are subject to different requirements for their operation and storage (climatic, sanitary and hygienic, fire safety, technical, technological, etc.).

Let's consider the basic materials of storage media and their forms.

Carriers images:

1. Paper . Historians say that paper was invented in China about 2,000 years ago. However, much earlier (approximately starting from VIII century AD), the ancient Egyptians made scrolls from papyri, where the word for paper “papier” comes from. Then the basis of paper media was rice straw, bamboo, rags,wood and other materials.

Synthetic (polyethylene) paper began to be used industrially abroad in April 1967. The fibers of the material, called " Tyvek» ( Tyvek ) have a thickness (diameter) of 0.5–1 µm. This is a smooth and opaque material that has absorbed the best properties of film, paper and fabric. It has a low specific gravity, high strength, resistance to punctures, tearing and abrasion, vapor permeability, water-repellent properties, resistance to rotting and biological inertness. Experts say that this material can replace traditional paper, especially in the manufacture of envelopes and any printing.

The material is resistant to most chemicals and is suitable for varnishing, laminating, heat sealing and gluing. It retains strength and flexibility up to a temperature of 73°C. It is believed that it is most suitable for street advertising, covers of textbooks, geographical maps, guidebooks, etc., since it does not fray on the folds and does not deteriorate from water. However, to print on such material you have to use special inks.

Similar material " Polylit» ( Polylith ) imported to Russia in 1998. It is made from polypropylene resin, mineral hardened with a mixture of neutral calcium and titanium dioxide to give a white and matte finish. It is the cheapest of synthetic materials and is resistant to water, heat, oil and chemicals. Another similar material is “ Robuskin» ( Robuskin ), an important distinguishing feature of which is the ability to print on it with conventional inks, practically without adjusting the printing equipment used for ordinary paper. There are, of course, other synthetic materials, including those with a self-adhesive base.

Paper backing is used in books, manuscripts, maps, diagrams and other similar documents. From the beginning of the appearance of manuscripts and books to the middle XIX centuries they were created mainly on paper from cotton and linen fibers. This is a "durable" paper. From the end of the 19th and 20th centuries, paper was mainly used as a medium. sulfite pulp and wood pulp. Modern books are mainly used as a medium cellulose materials.

2.Canvas, cardboard, hardboard and other art materials , on which paintings are painted, engravings and etchings are printed, are usually specially processed materials from woodworking (cardboard, hardboard) and weaving (canvas) industries. In addition, waste is used as a material for these purposes. wood(first) and flax or the like (second). In this case, the canvas is coated with a special compound (primed) before applying paints to it.

3. Photographic materials (negative, positive) are used for such media as photographic plate, photographic film, film or filmstrip, transparencies or slide, microfilm or microfiche. For these media, films are mainly used. cellulose, polyester based.

4. Gramophone record usually made by pressing from plastic mass(vinyl). It represents a round disk, on the surface of which concentric (spiral) grooves are applied, running from the outer side of the disk to its center. Discs differ in diameter, recording speed, number of audio channels and content.

By sizeThese discs are divided into three types:

1. “Giant” – 30 cm in diameter (playing time for one side is 25–30 minutes).

2. “Grand” – with a diameter of 25 cm (playing time for one side is 12–15 minutes).

3. “Minion” – with a diameter of 17.5 cm (playing time for one side is 6–8 minutes).

By disk rotation speed There are 4 types of gramophone records: 16, 33, 45, 78 rpm.

By type of record Records are divided into: monophonic, stereophonic and long-playing. Long-playing records have narrower grooves and a smaller distance between them (the pitch) than regular records, which allows the sound to last longer. Stereo records contain two-channel recording (left and right channels along the left and right walls of the groove).

5. Hologram – a plate with lithium niobate crystals or photopolymer film. Holographic memory, unlike CD technology, represents the entire volume of the storage medium of the media, with data elements being accumulated and read in parallel. It allows you to store 1 TB (a trillion bytes) in a crystal the size of a sugar cube, that is, more than 1000 CDs of information. Modern holographic storage devices are called HDSS (holographic data storage system).

6. Magnetic tapes in audio and video cassettes, streamers, magnetic disks floppy disks for PCs are made of synthetic materials with a magnetic layer (usually iron oxide) on lavsan or vinyl basis. HDD disks are made of light metal (aluminum) or glass and coated on both sides with a magnetic layer.

7. Magneto-optical disks (MO disks) are placed in a plastic case. Writing by a laser with a temperature of approximately 200°C onto the magnetic layer occurs simultaneously with a change in the magnetic field. This property ensures high reliability of storing recorded information.

8. IN optical (laser) disks – CDs for audio-video recordings and other machine-readable information. The media used in CDs is polycarbonate, polyvinyl chloride or special glass with a reflective (sprayed) layer of aluminum. They use an optical recording method. They can be classified as a medium, a carrier of various text, digital, sound and video recordings, multimedia, etc.

Distinguish between: AudioCD CD-ROM, CD-R, CD-R W et al.

CD- ROM. CD-ROM replication technology is similar to the production of gramophone records - printing (stamping) from matrices. During the recording process, the laser acts on the photoresist, leaving marks on it. The photoresist layer is developed and metalized. Then, using the electroplating method, a second one is made from the original - completely metal, and intermediate copies are created from it by stamping. From them, many matrices are created, from which manufactured products are replicated onto CDs.

CD-Rused for one-time laser recording or one-time recording with the addition of several recordings to the same disc in the form of sessions (additional recording).

CD-RWallow you to erase and write information on them many times (hundreds and thousands of times).

CDs are distinguished by their high recording density (about 300 thousand pages of text in A4 format), the ability quick search information stored on them (several milliseconds), durability of the media (tens of years).

This medium has up to four recording layers and a capacity from units (4.7) to tens (17) GB. In this case, the recording duration increases to 8 hours. Increasing the information capacity of the disc is achieved through the use of a laser with a shorter radiation wavelength (0.635–0.66 instead of 0.78 microns), as well as video data compression technology in the standards MPEG , which made it possible to increase the density of data recording on these disks and the speed of reading information from them. For example, the digital video data transfer rate is 1.3 Mb/s, which provides high quality video (better than VHS ), and on a monitor it is better than on a television receiver.

There are many types of CDs, differing in the use of different media materials, recording methods, etc. Among the new devices, it should be noted “Blu- rayDisc».

Blu-ray Disc technology developed at the end of 2001. Since February 2002, its specification has been supported by a number of well-known foreign companies. Discs with a diameter of 12 mm have a capacity of 23.3; 25 and 27 GB, the thickness of the transparent protective layer is 0.1 mm, and the track width is 0.32 mm, which made it possible not only to provide greater capacity, but also to increase the read/write speed. The basic speed of devices for working with these disks (1x) is 36 Mbit/s (5.5 MB/s). Let us remind you that DVD this parameter is 1.3 Mb/s, and CD – 150 KB/s respectively. According to the developers, these discs are well suited for recording television and video programs broadcast in digital format.

9. Flash -memory – solid-state built-in and replaceable thin memory wafer made of semiconductor materials. Contains a flash memory chip with contacts exposed to the outside. These cards receive power from the devices they connect to. The volume of stored information is from 16 MB to 4 GB.

Information is recorded and stored on different media using different methods. Storage forms and storage media are presented in Table. 5-2.

Table 5-2

Storage forms and media

Information form	Storage medium	Information recording method
Mechanical	plate	analog
Optical	paper	sign-symbolic
	film film	analog
	laser audio disc CD-A	analog
	laser disc CD-ROM, DVD	digital
Magnetic	audio video tape	analog
	floppy disks	digital
	hard drives	digital

The possibilities of using various media and their materials for recording and using even one type of data are very diverse. So, text can be recorded on almost any storage medium, presented as a static or dynamic image on the following storage media materials (Fig. 5-2).

Rice. 5-2. Text media materials

Sound, recorded on various media, is an important component of various funds and collections. Such media may be provided to users and used for business purposes; be stored for a short or long time, etc.

Audio recordings and gramophone records, available in one copy, are not recommended to be issued to users at home. It is better for information services serving users to purchase sound recordings in at least two copies in order to keep one of them in a reserve fund. If they contain gramophone records in one single copy, then it is advisable to rewrite them, for example, onto a magnetic tape, floppy disk or disk to replenish the main fund of sound recordings provided to users, and store the first copy in the reserve fund.

The sound is recorded and stored on the storage media shown in Fig. 5-3.

Rice. 5-3. Audio media

If the information services serving users have high-quality tape recorders or music centers, one purchased copy of a sound recording on magnetic tape is stored in a reserve fund, and copies are made from it in-house and issued to users.

Static video information obtained in the process of photographing and processing photographic materials (developing and printing). Until the mid-1930s, many photographic materials were produced on a cellulose-nitrate basis (film on a nitrate basis was produced until 1951). In the late 1940s, silverless powder photography appeared - xerography. In the 1950s, a way to create short-lived copies appeared - thermography.

A type of photography is micrography. Photographic recording allows documents to be stored in the form of microfilm and microfiche, i.e. microforms – microcarriers. Micromedia are copies of various originals (manuscripts, drawings, drawings, printed texts, etc.) obtained by photographic methods, reduced by tens and hundreds of times.

Microforms serve as a protective copy of the original. The basis of micrographic film is plastic bases. It is the most important factor determining the durability and safety of the film. Insurance (archival) funds store first-generation reference negatives (master negatives), which are used for microfilming manuscripts, archival materials and rare publications.

Vesicular, photothermoplastic and electrophotographic films are also used in micrography. They are mainly used for working microforms. Micromedia is used in information centers, archives, libraries, research, design and other institutions.

Relatively cheap and widespread types of audio and video storage media are magnetic tapes and disks. They are easy to use. Reliable methods have been developed to physically protect magnetic media from damage, errors during reading, and spontaneous disappearance of data. Thus, it is recommended to carefully wind, clean and rewind magnetic tapes in both directions every six months, and copy every 12 months. The UK Government Electronics Agency estimates that magnetic tapes can be stored for up to three years under normal conditions, but recommends that samples be tested every 18 months.

The modern way of recording audiovisual data presented to users is to “digitize” it and then record it on CDs. Work on creating a method digital recording and sound reproduction have been intensively carried out since the early 70s of the twentieth century. At the end of 1982, the first CDs went on sale.

The life of CDs can be significantly reduced by excessive heat, humidity, or direct sunlight. Therefore, it is recommended to store discs in a cool, dark and dry place.

With this article our site continues the whole cycle useful materials, the purpose of which will be to facilitate the choice of any product from thousands of options offered on the market. Agree, choice specific model Some device always takes a lot of time, which could be spent usefully. In today's article we will talk about choosing USB flash drive - “flash drives”.

Introduction

As is the case with external hard disks, USB drives have lost a significant part of their importance in our time - transferring information from one device to another today is much more convenient with the help of cloud Internet services. But this method may still be either inaccessible or too complicated for inexperienced users, but a “flash drive” is both simple and understandable.

Again, the operating speed of modern USB drive models significantly exceeds the speed of access to global network Internet of most users. In addition, flash drives can be used to quickly and conveniently transfer media content between home devices. Want to watch photos or videos on TV? There is no need to set up a DLNA server or worry about connecting an HDMI cable - just use a USB drive.

At first glance, choosing a “flash drive” is a trivial matter; you just need to find the cheapest model with the largest amount of memory for storing data. But the models on sale differ greatly in their speeds for writing and reading data - sometimes several times. In addition, “flash drives” can use cases of many different designs and designs - some can be quite large, others very compact, some elegant and shiny, others practical and secure.

In the next section, we will talk about the important technical characteristics of USB flash drives, and then present to your attention 10 best models all price categories.

Key Features of USB Flash Drives

Interface

USB flash drives can use USB 2.0 or USB 3.0 interfaces, as well as microUSB and Lightning (optional). USB 2.0 is already outdated - it is not recommended to buy models that only support this interface - the information transfer speed in its case is severely limited. USB 3.0 has been the standard for several years now.

A regular USB connector can be combined in one model with a microUSB or Lightning connector - located, for example, on the other side of the case. MicroUSB is useful for connecting a flash drive to smartphones and tablets, and Lightning is useful for, say, Apple devices.

Memory capacity

The main characteristic of any flash drive. Over many years of development of flash memory, its maximum capacity in USB drives has reached incredible heights - you can now carry a whole terabyte of data in your pocket. Naturally, for such a huge volume you will have to pay a fairly large amount - in our catalog, for example, it is proposed to pay more than 20 million rubles for the Kingston DataTraveler HyperX Predator 1TB.

“Flash drives” with 16, 32 or 64 GB of memory are much more affordable and practical. Most likely, you are unlikely to need a drive with a memory capacity of less than 8-16 GB, but you shouldn’t overdo it either - say, about 15 movies in excellent quality can fit on 128 GB of memory.

Data read and write speed, MB/s

Characteristics that manufacturers of cheap but bulky flash drive models prefer to keep silent about. The best representatives of devices in this category are characterized by at least 100 MB/s (read speed) and 50 MB/s (write speed) - you usually shouldn’t settle for anything less (of course, if you only transfer all sorts of documents to a flash drive, then too large speeds will not be needed). If you plan to use a flash drive to transfer large files like movies, then you should take a closer look at faster options. You will learn about the fastest USB flash drives in just a few paragraphs.

ReadyBoost support

This technology, developed by Microsoft, allows you to use a high-speed flash drive as storage for the Windows system swap file. Fortunately, by now the need to use USB drives in this way has simply disappeared - users are increasingly buying fast SSD drives that cope with loading the OS and processing data much better.

Password protection and data encryption

If you plan to use your future “flash drive” to transfer any information that should not under any circumstances fall into the wrong hands (for example, work documents or personal photos), then this function will definitely be useful. Files encrypted with a long key will simply be impossible to decrypt if the password is unknown - even the most powerful supercomputers in the world may now need many years to do this. Some models of USB drives were even equipped with a fingerprint scanner, but this practice did not catch on.

Dimensions, design, body material

Based on these parameters, it is difficult to recommend something - some like a strict industrial design, some like bright colors, some are more suited to a very small flash drive, others will be more comfortable working with larger models.

Waterproof case

If you lead an active lifestyle, you've probably at some point dropped your electronic devices in water or simply, say, forgotten that they were in your pocket. A flash drive with a waterproof casing will reliably protect your data in any conditions.

10 Best USB Flash Drives

Not too expensive and very fast (both USB 2.0 and USB 3.0) “flash drive” with the ability to protect user information with a password. Perfect for any task - and it looks very attractive.

The most compact USB flash drive ever presented. It is distinguished not only by its low cost and acceptable speed, but also by the ability to connect to microUSB ports - transferring data between your PC and a smartphone or tablet will be as easy as shelling pears.

With a metal body, high speeds, low cost and an elegant design, this Adata model is definitely worth a look and can be used for almost any purpose.

Another inexpensive and fairly fast model with an attractive design, metal body and retractable connector. As a bonus, it comes with a ring for attaching to your keychain.

If you are attracted by bright design and large capacity for little money. Unfortunately, although the JetFlash 760 uses USB 3.0, it can only write information at speeds of up to 25 MB/s - this explains its low cost.

A cheap and compact flash drive, the data on which can be protected with a password. Unfortunately, it uses USB 2.0 and writes information at a speed below 10 MB/s.

Metal body, USB 3.0, low cost and high capacity - all this is compensated by not the fastest write speed, which in the case of the S102 Pro is about 25 MB/s.

A very fast and quite expensive model with an interesting design. Unfortunately, it does not support data protection with a password or encryption - it is just a very high-speed and large, but quite affordable USB drive.

A very, very high-speed and expensive USB drive with a huge capacity. It is clearly clear that this is a premium model - you are mainly offered to pay for the brand and stylish design (the case, by the way, is metal).

The fastest “flash drive” presented in our review - the data writing speed in its case reaches 240 MB/s (!). Password protection of data is also supported. Bonus - metal case, retractable connector and very stylish appearance. Naturally, you will have to pay for all this - Extreme PRO costs about one and a half million rubles, but in its case this money is perhaps more than justified.

Conclusion

We hope this article helped you understand the difficult task of choosing a USB flash drive. The next article will talk about

A USB flash drive or simply a flash drive is a data storage device that is based on flash memory and a USB interface for physical connection with a computer or other device.

General understanding of USB flash drive

USB flash drives are typically removable and rewritable, and are smaller in size than an optical disk. Purpose USB flash drives the same as legacy floppy disks and optical disks, i.e. for storing information, backup copies and transferring files. They are smaller than their counterparts, faster and, like SSDs, have no moving parts. At one time, floppy disks were abandoned due to their exposure to electromagnetic interference and low capacity in favor of USB storage devices.

USB flash drives are supported by all modern operating systems: Windows, Linux and OS X. USB flash drives can work without problems with game consoles, audio-video players, as well as on most types of computers.

This flash drive consists of a small printed circuit board with connected elements and a USB plug protected from external influence, body (made of metal, plastic, there are devices with rubberized bodies and leather covers, which is suitable for always carrying with you or as a key fob).

The USB plug may be protected by a cover or have a mechanism that is often present to retract into the housing, which provides additional protection. A connection type called USB allows you to connect to anything that has a compatible port. USB flash drives are powered by a connection; other devices, including portable audio-video players, also use this charging feature. Most of them can be used as a flash drive, only with a battery to ensure battery life.

The emergence of a USB flash drive

The invention of USB flash drives was patented by the inventors of the Israeli company M-Systems: Dov Moran, Amir Ban and Oron Ogdan in April 1999, but this device was externally different from modern USB flash drives. Later, on September 13, Shimon Shmueli already patented a design that accurately describes the USB flash drive that is used today. Due to disagreements and disputes over determining the authorship of a given medium, litigation was not uncommon.

The first such storage devices became available in 2000, the volume was equal to 8 megabytes, which is about 5 times more than floppy disks used at that time. By 2013, most flash drives had a USB 2.0 interface with a possible speed of 480 Mbit/s.

Although oh the advent of USB 3.0 flash drives were announced back in 2008; they became available to consumers only in 2010. The advantage of the USB 3.0 interface is the data transfer speed of 5 Gbps and backward compatibility with USB 2.0. Most modern computers have at least one such port. But already in March 2015, it was announced the production of USB flash drives, with USB 3.1 plugs providing even higher data transfer speeds.

Using USB flash drives

The most common use of flash drives is to transfer and store any files. Flash drives are often used to update BIOS or UEFI of motherboards.
Most modern PCs support not only installing an operating system using a bootable flash drive, but the ability to boot from a USB device, which allows the operating system to boot from a flash drive. This configuration is often called Live USB among users. This feature will help not only in cloning an operating system and then transferring it to a similar computer, performing file manipulations without loading the main OS and fighting malware.
The USB storage device supports encryption, which is important for secure storage of information and does not lose its relevance during backup. Flash drives can be used as a key for activating (USB Keys) applications.

Capacity of USB flash drive

As mentioned earlier, since 2000, flash drives have had a capacity of 8 megabytes. Later, the maximum volumes increased by 2 times (16 MB, 32 MB, 64 MB, etc.) Although the possible volumes are already over a terabyte, USB flash drives from 8 to 120 gigabytes are still successful with buyers.

How does a flash drive work and its main components?

The most common flash drive has a Standard-A USB interface, but there are also those that have micro-USB interfaces; such standardization can facilitate transfer between different devices. Underneath the case is a small printed circuit board on which integrated circuits and power circuits are located. As a rule, the most ordinary flash drive consists of five parts:

1. The plug, most often A-USB, with via USB The interface provides a physical connection to the computer;
2. Microcontroller with a small amount of RAM and ROM;
3. NAND flash memory chips that store user information;
4. Quartz (crystal) oscillator - produces clock frequency 12 MHz (generates clock pulses);
5. The housing, which is usually made from plastic or metal, thereby protects the electronics from mechanical stress.

Non-core components may include various LEDs that flash when accessing a USB flash drive, switches that can block or unlock access. A cover covering the USB plug is not necessary, but it is a kind of protection for the plug. Some USB flash devices have a through hole, which makes them like a keychain or for attaching a cord to it. There are also flash drives that have memory expansion functions, into which you can add an SD card, just like readers (card readers).

Dimensions and appearance of the flash drive

The usual USB flash drive usually has an elongated shape, but some manufacturers draw the attention of their customers to the unusual appearance of their USB flash drives, or rather the unusual case, which can be so bulky that it creates some difficulties when connecting devices. This is due to the fact that USB connectors on a computer it is often very close to each other, so two ports can be occupied by one USB flash drive. Flash drives are often integrated into other technical solutions, such as watches, pens, etc. Shapes, colors and images are limited only by the imagination.

Flash drive and its file system

Most flash drives initially have the FAT32 or ExFAT file system, this allows you to use the flash drive on almost any USB-enabled device, however file system can be any supported operating system.

Read and write speed

Data read and write speeds are measured in megabytes per second (MB/s), and the read speed is usually greater than the write speed, and the characteristics declared by the manufacturer, obtained under optimal conditions, may also differ from the actual ones. The speed of operation is also affected by the version of the USB interface.

What does the service of a USB flash drive depend on?

Cheap flash drives are usually designed using multi-level memory cells, implying up to 5000 sector write and erase cycles. Drives designed using single-level memory cells will be able to withstand 2 times more rewrite cycles. It all depends on the frequency of use of the flash drive; your descendants will also be able to use it if they use it extremely rarely.

The service life also depends on the quality of the flash drive itself. You can often buy a fake that does not meet the requirements of the original. In such USB media Memory sizes may differ from those stated, even if standard check shows the denomination, then after filling out the part or after formatting, the space may disappear. Supported interfaces may also differ from those declared: the declared USB 3.0 may ultimately work as 2.0.

What is a flash drive - it is a modern device for storing, transferring, encrypting, backup and even more functionality. All this makes life easier not only for the PC user, but also for the professional. You can often find a USB flash drive with the logo of some organization, this is quite good advertising, the main thing is to use only high-quality media, this will make it possible to save everything necessary information for many years.