What types of memory belong to a computer. Types of PC memory
7. Memory– an environment or functional part of a computer intended for receiving, storing and selectively issuing data. There are RAM, register, cache and external memory.
Functions and main characteristics of PC internal memory
Internal memory - This is memory that the processor can access directly during operation and use it immediately.
Internal memory includes:
1. RAM(RAM, English RAM, Random Access Memory - random access memory) - this fast storage device is not very large volume, directly connected to the processor and designed to record, read and store executable programs and data processed by these programs.
RAM is used only for temporary storage of data and programs, since when the machine is turned off, everything that was in the RAM is lost. Accessing elements RAM direct - this means that each byte of memory has its own individual address.
2. Cache(English cache) or ultra-fast memory is a very fast, small-volume memory that is used when exchanging data between a microprocessor and RAM to compensate for the difference in the speed of information processing by the processor and somewhat less fast RAM.
The cache memory is controlled by a special device - a controller, which, by analyzing the program being executed, tries to predict what data and commands the processor will most likely need in the near future, and pumps them into the cache memory. In this case, both “hits” and “misses” are possible. In case of a hit, that is, if the necessary data is pumped into the cache, it is retrieved from memory without delay. If the required information is not in the cache, the processor reads it directly from RAM. The ratio of hits to misses determines the effectiveness of caching.
Cache memory is implemented on SRAM (Static RAM) chips, which are faster, more expensive and lower-capacity than DRAM (SDRAM). Modern microprocessors have a built-in cache memory, the so-called first level cache of 8, 16 or 32 KB in size. In addition, on system board The computer can have a second level cache with a capacity of 256, 512 KB and higher.
Persistent memory(ROM, English ROM, Read Only Memory - read-only memory) - non-volatile memory, used to store data that will never require changes. The memory contents are specially “hardwired” into the device during its manufacture for permanent storage. ROM can only be read.
Species external memory PCs, their features and main characteristics.
External memory(VRAM) is designed for long-term storage of programs and data, and the integrity of its contents does not depend on whether the computer is turned on or off. This type of memory has a large capacity and low speed. Unlike RAM, external memory does not have a direct connection with the processor. Information from the OSD to the processor and vice versa circulates approximately along the following chain:
The computer's external memory includes:
1. Hard drive(hard magnetic disk drives, HDD) - a type of permanent memory. Unlike RAM, data stored on a hard drive is not lost when the computer is turned off, making hard drive ideal for long-term storage of programs and data files, as well as the most important programs operating system. This ability (keeping information intact and safe after shutdown) allows you to remove a hard drive from one computer and insert it into another.
The hard drive, or hard drive, is the most important component of a computer. It stores the operating system, programs and data. Without operating room Windows systems You can’t start the computer, and without programs you can’t do anything once it’s already booted. Without a data bank, you will have to enter information manually each time.
2. Disk drives (floppy magnetic disk drives (FDD), English FDD) come in two main types - for large floppy disks(size 5.25 inches, sometimes written - 5.25"), and for small ones (3.5 inches, 3.5"). A five-inch floppy disk can hold, depending on its type, from 360 information (360 thousand characters) to 1.2 MB. Three-inch cards, although smaller, hold more information (720 KB - 1.44 MB). In addition, the three-inchers are enclosed in a plastic case, and therefore are more difficult to break or dent. Standard drive for modern computers is a drive for small (3.5-inch) floppy disks. Hence its name in a computer system - 3.5 A drive.
3. Laser drives (CD-ROM and DVD-ROM) use the optical principle of reading information.
On laser CD-ROM (CD - Compact Disk, CD) and DVD-ROM (DVD - Digital Video Disk (digital video disc) disks store information that was recorded on them during the manufacturing process. Record on them new information is impossible, which is reflected in the second part of their names: ROM (Real Only Memory - read only). Such discs are produced by stamping and have a silver color.
There are CD-R and DVD-R discs (R - recordable) that are golden in color. Information on such disks can be written, but only once. On CD-RW and DVD-RW (RW - ReWritable) discs, which have a "platinum" tint, information can be recorded many times.
4. Magnetic tape drives (streamers) and removable disk drives
Streamer (English tape streamer) - a device for backup large amounts of information. The media used here are magnetic tape cassettes with a capacity of 1 - 2 GB or more.
Streamers allow you to record onto a small cassette tape. huge amount information. The hardware compression tools built into the tape drive allow you to automatically compress information before recording it and restore it after reading it, which increases the amount of stored information.
The disadvantage of streamers is their relatively low speed of recording, searching and reading information. At the moment, streamers are outdated and therefore they are used very rarely in practice.
ALL-RUSSIAN CORRESPONDENCE FINANCIAL AND ECONOMIC COURSE
INSTITUTE
DEPARTMENT OF AUTOMATED PROCESSING
ECONOMIC INFORMATION
COURSE WORK
in the discipline "Informatics"
on the topic “Classification of the main types of personal computer memory”
Option No. 11
Executor:
Kutepova Olga Konstantinovna
specialty MiM
group 217
Record book number 07mab03272
Supervisor:
Solovyova Evgenia Grigorievna
Introduction…………………………………………………………………………………..3
1. Internal memory of a personal computer…………………….4
1.1. Random access memory……………………….4
1.2. Read-only memory………………………..8
2. External memory of a personal computer……………………....10
Conclusion……………………………………………………………....………....14
List of references………………………..………..…..15
INTRODUCTION
Memory is one of ourselves important elements personal computer (PC). All PCs use three types of memory: RAM, ROM and external (various drives).
The device for storing information is called main memory, which consists of random access memory (RAM) and read-only memory (ROM).
On some microprocessor systems general purpose Almost all memory space is RAM. A write operation is used to write program instructions into memory. Further, during the execution of the program, the microprocessor will read commands from it. Data is also written to and read from memory areas. Almost all storage devices in microprocessor systems are random access memory. This memory received the name “RAM” because it works very quickly and therefore the processor practically does not need to wait when reading data from or writing to memory. Since a randomly selected cell can be accessed at any time, this type of memory is also called random access memory - RAM. (Random Access Memory). But the data contained in RAM is saved only while the computer is turned on or until the reset button is pressed. When you turn off the computer, the contents of the RAM are erased.
Read-only memory has its own name - ROM (Read Only Memory). This name indicates that it provides only read and storage modes and usually contains information that should not change for a long time. Further in this work we will consider in more detail the main types of memory of a personal computer.
1. INTERNAL MEMORY
Internal memory- this is high-speed memory and limited capacity; it can consist of RAM and permanent memory. The principle of its division is the same as in humans. We have some information that is stored in memory permanently, but there is information that we remember for some time, or it is needed only for the moment while we are thinking about solving a problem.
Random access memory is used to store operational memory that often changes during the process of solving a problem. When solving another task, the RAM will store information only for that task. When the computer is turned off, all information located in RAM is in most cases erased.
Read-only memory is designed to store permanent information that does not depend on what task is being solved in the computer. In most cases, permanent information consists of programs for solving frequently used problems, as well as some control programs, microprograms, etc. Turning off the computer and turning it back on does not affect the quality of information storage.
Main (RAM) memory chips always work slower than the processor. Therefore, the processor often has to idle clock cycles while waiting for data to arrive from memory. To partially solve this problem, small memory is used (about 128 - 512 KB), which is based on faster (and more expensive) memory chips. This kind of memory is called cache or ultra-RAM.
1.1. Random Access Memory (RAM or RAM )
RAM- fast, semiconductor, volatile memory. RAM has a relatively small volume - usually from 64 to 512 MB, however, the central processor has online (fast) access to data written in RAM (it takes no more than a few nanoseconds to retrieve data from RAM). RAM stores the currently executing program and the data with which it directly works. This means that when we run any computer program located on the disk, it is copied into RAM, after which the processor begins to execute the commands contained in this program. A part of RAM called "video memory" contains data corresponding to the current image on the screen. RAM is memory used for both reading and writing information. When the power supply is turned off, the information in the RAM disappears, which is explained by energy dependence.
The amount of RAM installed in your computer directly determines what programs you can work with on it. At insufficient quantities RAM, many programs will not work at all, or will work very slowly.
Often the designation RAM (Random Access Memory) is used for RAM, that is, random access memory.
Semiconductor RAM is currently divided into static RAM (SRAM) and dynamic RAM(DRAM) (Fig. 1).
Rice. 1. Classification of RAM
Dynamic RAM (DRAM) is used in most PC RAM systems. The main advantage of this type of memory is that its cells are packed very tightly, i.e. Many bits can be packed into a small chip, which means they can be used to build larger-capacity memories.
The memory cells in a DRAM chip are tiny capacitors that hold charges. The problems associated with this type of memory are caused by the fact that it is dynamic, i.e. must be constantly regenerated, otherwise electric charges The memory capacitors will “drain” and data will be lost.
The most important characteristic of DRAM is speed, or simply put, cycle duration + delay time + access time, where cycle duration is the time spent on data transfer, delay time is initial installation row and column addresses, and the access time is the search time for the cell itself. Measured in nanoseconds.
There is a type of memory that is completely different from others - static RAM (SRAM). It is so named because, unlike dynamic random access memory, it does not require periodic regeneration to retain its contents. But this is not its only advantage. SRAM is faster than DRAM and can run at the same speed as modern processors.
SRAM chips are not used for all system memory because, compared to dynamic random access memory, SRAM is much faster, but its density is much lower and the price is quite high. Lower density means that SRAM chips are larger, although their information capacity is much smaller.
Despite this, developers still use SRAM memory to improve PC performance. But to avoid significant cost increases, only a small amount of high-speed SRAM is installed, which is used as cache memory.
Translated, the word “cache” means “secret warehouse”, “cache”. The secret of this warehouse lies in its “transparency” - it does not add an addressable memory area for the program. The cache is an additional high-speed storage of copies of blocks of information from the main memory, the probability of which will be accessed in the near future is high. The cache cannot store a copy of the entire main memory because its size is many times smaller than the size of the main memory. It stores only a limited number of data blocks and a directory - a list of their current correspondence to areas of main memory. In addition, not all RAM available to the processor may be cached: firstly, due to technical limitations, the maximum amount of cached memory may be limited; secondly, some memory areas can be declared non-cacheable (by setting the chipset or processor registers). If there is more RAM installed than can be cached, accessing the non-cacheable area of RAM will be slow. Thus, increasing the amount of RAM, while theoretically always beneficial for performance, can reduce the performance of certain components that end up in non-cacheable memory.
Main memory consists of registers A register is a device for temporarily storing information in digitized (binary) form. The storage element in the register is trigger- a device that can be in one of two states, one of which corresponds to storing a binary zero, the other to storing a binary one. The trigger is a tiny capacitor battery that can be charged many times. If such a capacitor is charged, it seems to remember the value “1”; if there is no charge, the value “0”. The register contains several related friend with a friend of triggers. The number of flip-flops in a register is called the computer's capacity. Computer performance is directly related to the bit depth, which can be 8, 16, 32, 64, 128.
A few days ago I “freaked out” - I was tired of buying parts for the future home “supercomputer”. I took it and bought the remaining parts at once - the motherboard, processor and RAM.
Today I'll tell you how to choose RAM for a computer and even how to install it correctly.
What is RAM
Before choosing RAM for your computer, you need to clearly understand what it is in general.
RAM in a computer is one of the components, along with the central processor and SSD drive, which is responsible for the speed of the system.
The official definition goes something like this: RAM (Random Access Memory) is a volatile part of a computer system that temporarily stores the input, output, and intermediate data of programs and the operating system.
But, as always, I will try to convey this definition to you in simple language...
The processor is the brain of the computer that processes all information. Hard drive ( or SSD drive) stores all the data (programs, photos, movies, music...). RAM is an intermediate link between them. The data that needs to be processed by the processor is “pulled” into it.
Why do they “pull themselves up”? Why not take them right away? hard drive? The fact is that RAM works many times faster than even an SSD drive.
What data the processor may soon need is determined by the operating system itself, automatically. She is very smart, no matter what they say about her.
Types of RAM
When mammoths still walked the earth, RAM was divided into SIMM and DIMM - immediately forget about these types of RAM, they have not been produced or used for a long time.
Then DDR was invented (2001). There are also computers with this type of memory. The main difference from DDR2 and DDR3 is the number of pins on the board DDR memory, there are only 184 of them. This type of RAM is much slower than its modern counterparts (DDR2 and DDR3).
In DDR2 (2003) larger number contacts (240 pieces), thanks to this the number of data streams has expanded and the transfer of information to the processor has noticeably accelerated. Maximum frequency DDR2 is 1066 MHz.
DDR3 (2007) is the most common type of RAM in modern computers. Here they left the number of contacts alone (240 pieces), but made them electrically incompatible. Maximum DDR3 frequency – 2400 MHz . This type of memory also has lower power consumption and higher bandwidth.
DDR3 turned out to be 15-20% faster than DDR2.
DDR2 and DDR3 strips have different “key” locations, they are not interchangeable...
Form factor of RAM strips
RAM strips for laptops (SODIMM) and desktop computers (SDRAM) are different in size and appearance. For laptops they look like this...
...and for stationary home computers, something like this...
This is where their differences (mostly) end. The characteristics that you need to know to choose RAM are absolutely the same for these two types.
RAM capacity
In the last century, the amount of RAM was measured in kilobytes and megabytes (it’s even funny to remember). Today - in gigabytes.
This parameter determines how much temporary information will fit into the RAM chip. Everything is relatively simple here. Windows itself consumes about 1 GB of memory when running, so there should be more of it in the computer.
2 GB - may be enough for a budget computer (movies, photos, Internet)
4 GB - suitable for more demanding programs, games on medium and maximum settings quality
8 GB - will handle heavy games at maximum quality settings or very memory-demanding programs *DANCE*
16 GB - the newest modern and heavy games, as well as special professional monster programs, will “fly”
32 GB - You have nowhere to put your money? Send them to me.
It is very important to consider that regular 32-bit operating systems Windows “does not see” memory more than 3 GB and, accordingly, does not use it. If you buy more than 3 GB of RAM, you MUST install a 64-bit system.
RAM frequency
Inexperienced users are often limited by its size when choosing RAM, but memory frequency is no less important. It determines at what speed data will be exchanged with the processor.
Modern regular processors operate at a frequency of 1600 MHz. Accordingly, it is advisable to buy memory with such a frequency, no higher (1866 MHz is possible). The difference between 1333 MHz and 1600 MHz is almost invisible to the eye.
As for memory sticks with a frequency of 2133 MHz and higher, they themselves cost a lot of money, for them full-fledged work you need special motherboards, which cost crazy money, and most importantly, you need a processor with an unlocked multiplier (supporting overclocking), which costs...
At the same time, all this disgrace will get very hot (you need a powerful cooling system (preferably water), which costs...) and consume a lot of energy. This is the choice of crazy gamers.
By the way, the increase in computer performance with such overclocking will be only from 10 to 30%, and you will spend three times more money. Do you need it?
RAM timing
A “terrible” parameter of RAM that few people know about and which is rarely taken into account when choosing memory, but in vain.
Latency (timing) is the time delay of a signal. It is measured in beats. The timings can take values from 2 to 13. The throughput of the “processor-memory” section and, as a result, the performance of the system depend on them, although quite a bit.
The lower the timing value, the faster the RAM works. For example, I purchased memory with timing values 9-9-9-24, but there are faster ones, of course.
RAM timings can be adjusted in the BIOS when overclocking the system (this is not recommended for inexperienced users).
And at the end of the article, as I promised at the beginning, I’ll tell you...
How to properly install RAM in a computer
Before the procedure, be sure to turn off the computer and disconnect the power cord from system unit.
There is no need to make any settings in the system after installing the memory. The system itself will recognize it and start using it.
The easiest way to install memory is in a laptop (it can be more difficult to open the back cover). In laptops the RAM is in horizontal position, lies.
Simply lift and pull it out of the grooves, insert the new one until it stops. The lock on the bar (slot) will prevent you from making mistakes when installing...
On desktop computers this process is a bit more complicated. The memory stands vertically to motherboard and secured with latches.
To remove the strip, just move these latches to the sides and it will “jump” out of the slot. Installation will also take you 2 seconds - bring the bar to the slot, match the lock (slot) on the bar with the jumper in the slot and insert it all the way (you will hear a click - the latches will clamp the bar).
It is very important not to confuse the click of the clamps with the crunch of a broken motherboard.
Dual channel memory mode
Personal computer memory. Memory is designed to store programs and data that the processor directly works with. It consists of cells whose location is determined by a unique address. In addition to temporary data, which is determined by what the computer is currently doing, it must know and constantly remember some standard programs and data. Solving the problems of storing various types of information and reliable functioning of a personal computer has led to the use of several types of internal and external memory
Internal memory RAM is designed to store information and is implemented using a set of chips installed on the motherboard. Memory modules are plates with rows of contacts on which large integrated circuits memory. Random access memory (RAM) Read-only memory (ROM) Cache memory
The memory of the random access memory device stores temporary information that changes during execution by the microprocessor various operations. This kind of memory provides access to any randomly selected memory cell at any time. This property is reflected in the English name of the operational RAM memory(Random Access Memory - random access memory). We must not forget that RAM is a volatile device, i.e. when the computer is turned off, all information in the RAM is erased. RAM is characterized by high speed and relatively small volume. For modern computers, the memory capacity range is 16 - 512 MB. RAM
The ROM memory stores information recorded at the manufacturer; it must remain unchanged for a long time. Persistent information includes basic system programs that automatically start when you turn on the computer. The computer can read or execute programs from permanent memory, but it cannot change them or add new ones. ROM memory is intended only for reading information. This property of persistent memory explains the frequently used English name ROM (Read Only Memory). ROM memory is also implemented in the form of integrated circuits. The difference is that these chips are non-volatile. Turning off the power does not result in data loss. There are two main types of ROM memory chips, once programmable (once written, the contents of the memory cannot be changed) and repeatedly programmable. ROM
Cache memory To increase computer performance and coordinate the operation of devices with different speeds, a modern computer uses another type of memory - cache memory (from the English cache - hiding place, warehouse). Cache memory is an intermediate storage device or buffer. It is used when exchanging data between the microprocessor and RAM, between RAM and an external storage device. Using cache memory reduces the number of accesses to hard drive for read-write, since it stores data, repeated access to which on the part of the processor does not require repeating the reading process or other information processing. There are two types of cache memory: internal (from 8 to 64 KB), located inside the processor, and external (from 256 KB to 1 MB), which is installed on the motherboard. microprocessor RAM External storage
External memory External memory is designed for long-term storage of programs and data. External memory devices (drives) are non-volatile; turning off the power does not lead to data loss. They can be built into the system unit or made in the form of independent units connected to the system unit through its ports. An important characteristic of external memory is its volume. The amount of external memory can be increased by adding new drives. No less important characteristics of external memory are the access time to information and the speed of information exchange. These parameters depend on the device for reading information and the organization of the type of access to it.
NGMD Flexible magnetic disks, or floppy disks ( floppy disk), are the most common storage media. The most popular floppy disks are 3.5" (inch), (3-inch). The disks are called flexible because the plastic disk located inside the protective sleeve actually bends. That is why the protective sleeve is made of hard plastic. The disk is covered on top with a special magnetic layer, which provides data storage. Information is recorded on both sides of the disk along tracks that are concentric circles. Each track is divided into sectors. The density of data recording depends on the density of the tracks on the surface, i.e., the number of tracks on the surface of the disk. also on the density of information recording along the track. There are DD, HD and ED standards for 3.5" floppy disks, the volume of recorded information is from 720 KB to 2.88 MB. The most common are 3.5" HD floppy disks. As a storage medium, floppy disks are almost obsolete. themselves, small volume, low read/write speed, and unreliability make their use unprofitable.
HDD Hard magnetic disks, or “hard drives,” are an essential component of a personal computer. There are different versions origin of the name "Winchester". According to one of them, the first hard drives were released at an IBM branch in the small town of Winchester. A hard drive is several aluminum plates coated with a magnetic layer, which, together with the reading and writing mechanism, are enclosed in a hermetically sealed case inside the system unit. Hard drives have advantages over floppy disks according to two main parameters: volume hard drives significantly higher and ranges from several hundred megabytes to hundreds of gigabytes; the speed of information exchange is 10 times greater. The hard drive is accessed using the name specified Latin letter WITH: . If installed second hard disk, it is assigned next letter Latin alphabet D: . The computer provides the ability, using a special system program conditionally split one disk into several. Such disks that do not exist as a separate physical device, but represent only part of one physical disk, are called logical disks.
CD-ROM CD-ROM drives. Compact discs, which were used for audio equipment, were modified for use in PCs and have now become an integral part of modern computers. It is an excellent storage medium, more compact, convenient and cheaper than a hard drive. It is designed as an internal device and has a 5.25" drive size. Usually managed via IDE, SCSI interface or sound card. The disc is made of polycarbonate, which is coated on one side with a reflective layer (made of aluminum or gold). Recording is carried out using a laser beam that burns alternating depressions in the surface of the metal layer. The main characteristic is the data transfer speed. The reading unit is the reading speed from a magnetic tape. The reading speed of subsequent devices is a multiple of this and varies from 150 KB. /sec. Up to 6 -7 MB. /sec. The quality of reading is characterized by the error rate and is an estimate of the probability of distortion of an information bit when it is read. This parameter reflects the device's ability to correct read/write errors. Average access time is the time it takes for the drive to find the necessary data on the media. Varies from 400 to 80 ms.
DVD-ROM DVD (Digital Video Disk) - discs that will replace CD-ROM, were originally developed for home video. They differ in that they can store a volume of data many times greater than the capabilities of CDs (from 4.7 to 17 GB). The level of sound and image quality stored on DVD is close to studio quality. IN DVD drives a narrower laser beam is used than in CD-ROM, so the thickness of the protective layer of the disc was reduced by 2 times, which led to the appearance of double-layer discs.
Flash memory Flash memory, introduced in the late 1980s (Intel), is a member of a class of electrically erasable programmable read-only memory devices. However, it erases an entire area of cells at once: a block or the entire chip. This ensures faster recording of information or, as this procedure is otherwise called, memory programming. To simplify this procedure, special blocks are included in the chip that make the recording “transparent” (similar to recording in a regular memory) for the hardware and software environment.
Various types flash memory Portable DVD-ROM drive; can be used both when connected to a computer as a DVD-ROM, and as a DVD player when connected to a TV. DISK STENO is nothing more than a stand-alone external USB 2.0 CDRW drive combined with a 6-format card reader. Can read information from six main types of flash cards, can also be used as an external write drive. ZIP Pro drive. Can perform simple tasks that involve moving things here and there small volumes work data and large amounts of entertainment data such as music, movies and games.
Nixvue Digital Album Flash Cards Once a memory card (used, for example, in a digital camera) is full, data from that card can be copied to a digital album; It is possible to print photos without a computer. OLYMPUS CAMEDIA MXD 512 P x. D-Picture Card A memory card designed for long-term (tens of years) data storage in the absence of a power source. Used in digital cameras and other devices. USB Flash Drive Resource - up to 1,000 rewrite cycles. The guaranteed data storage period is up to 10 years. Smart. Media Flash Card A memory card designed for long-term data storage. Used in digital cameras and other devices Compact Flash Card Memory card designed for long-term (tens of years) storage of data in the absence of a source. Used in digital cameras pocket computers and other devices SD Memory Card Memory card; used in MP3 players, digital cameras, PDAs, smartphones and other devices.
Memory (computer)
RAM module inserted into the motherboard
Computer memory (storage device, memory) - part of a computer, a physical device or medium for storing data used in calculations for a certain time. Memory, like the CPU, has been a constant part of the computer since the 1940s.
At the everyday level, the word “memory” has a narrower meaning - semiconductor random access memory (RAM), used as RAM on a personal computer (memory stick or memory module). However, the concept of memory is much broader.
Computer memory has always had a hierarchical structure and involves the use of several storage devices with different characteristics.
The most well-known means of machine data storage used in personal computers are: RAM modules, hard drives (hard drives), floppy disks (floppy disks), or flash memory.
Memory functions
Computer memory provides support for one of the functions of a modern computer - the ability to store information for a long time. Together with the central processing unit, the storage device is the key element of the so-called von Neumann architecture, the principle underlying most modern general-purpose computers.
The first computers used storage devices solely to store processed data. Their programs were implemented on hardware level in the form of strictly defined executable sequences. Any reprogramming required a huge volume self made for the preparation of new documentation, reconnection, restructuring of blocks and devices, etc. Use of von Neumann architecture, which provides storage computer programs and data in shared memory, radically changed the situation.
To date, many different devices have been created for storing data, many of which are based on the use of a variety of physical effects. Universal solution does not exist, each contains certain shortcomings. Therefore, computer systems are usually equipped with several types of storage systems, the main properties of which determine their use and purpose.
Physical basis of functioning
Read Only Memory, ROM is a type of storage memory designed to store and read data that never changes. Data is written to ROM during its manufacturing process, so it cannot be changed by the user. The most common ROMs made on integrated circuits(LSI, VLSI) and optical disks CD-ROM and DVD-ROM.
Programmable Read Only Memory, PROM is a type of memory in which data can be written or changed by exposing the storage medium to electric, magnetic and/or electromagnetic (including ultraviolet or other) fields, often under control special program. There are write-once EPROMs and erasable EPROMs. EPROM, Erasable PROM ), including:
- Electrically programmable ROM (EPROM) Electrically Alterable Read Only Memory, EAROM )
- Electrically Erasable Programmable ROM (EEPROM) Electrically Erasable Programmable Read-Only Memory flash memory
), different high speed access and the ability to quickly erase data
By energy dependence
Holographic memory(English) holographic storage) - spatial graphic information displayed in the form of interference structures is used as a recording and storage medium.
Matrix memory(English) matrix storage) - a type of memory whose elements (cells) are arranged in such a way that they are accessed along two or more coordinates.
Multi-block memory(English) multibunk memory) - a type of RAM organized from several independent blocks that allow simultaneous access to them, which increases its throughput. The term “interliving” (tracing paper from English) is often used. interleave- interleave) and can be found in the documentation of some companies “multi-channel memory” (eng. Multichanel).
Multi-input memory(English) multiport storage memory) - a memory device that allows independent access from several directions (inputs), and requests are serviced in order of their priority.
Multi-level memory(English) multilevel memory) - a memory organization consisting of several levels of storage devices with different characteristics and viewed by users as a whole. Multi-level memory is characterized by a page organization, which ensures “transparency” of data exchange between memories of different levels.
Directly managed (RAM) memory(English) on-line storage) - memory directly accessible to the central processor at a given time.
Object-oriented memory(English) object storage) - memory, the management system of which is focused on storing objects. Moreover, each object is characterized by the type and size of the record.
Overlay memory(English) overlayable storage) - a type of memory with overlapping called in different times software modules.
Parallel memory(English) parallel storage) - a type of memory in which all search areas can be accessed simultaneously.
Reloadable control memory(English) reloadable control storage) - a type of memory designed for storing control microprograms and allowing multiple changes of content - automatically or under the control of the computer operator.
Relocatable memory(English) data-carrier storage) - a type of archival memory in which data is stored on a relocatable medium. There is no direct access to them from the computer.
Sequential memory(English) sequential storage) - a type of memory in which data is written and retrieved sequentially - digit by digit.
CPU memory, processor memory(English) processor storage) - memory, which is part of the processor and is intended for storing data directly involved in the execution of operations implemented by the arithmetic-logical unit and control device.
Memory with built-in logic, functional memory(English) logic-in-memory) - a type of memory containing built-in means of logical processing (transformation) of data, for example, their scaling, code conversion, overlaying fields, etc.
Working (intermediate) memory(English) working (intermediate) storage ):
- A part of computer memory intended for storing temporary data sets.
- Memory for temporary storage of data.
Real memory(English) real storage) - all physical memory The computer, including main and external memory, accessible to central processor and designed to host programs and data.
Register memory(English) register storage) - a type of memory consisting of general-purpose registers and floating-point registers. As a rule, it is contained entirely within the processor.
Free (available) memory(English) free space) - an area or space of memory that can currently be allocated for loading a program or writing data.
Semantic memory(English) semantic storage) - a type of memory in which data is stored and written off in accordance with a certain structure of conceptual features.
Shared memory(English) shareable storage) - a type of memory that allows simultaneous use its multiple processors.
Protected memory, protected memory(English) protected storage) - a type of memory that has built-in means of protection against unauthorized access to any of its cells.
Memory with sequential access (English) sequential access storage) - a type of memory in which the sequence of input messages and data samples addressed to them corresponds to the sequence in which their records are organized. The main method of searching for data in this type of memory is sequential enumeration of records.
Direct access memory, random access memory (RAM)(English) Random Access Memory, RAM) - a type of memory in which the sequence of input messages and data samples addressed to them does not depend on the sequence in which their records are organized or their location.
Word-based memory(English) word-organized memory) - a type of memory in which addressing, recording and retrieving data is carried out not byte by byte, but word by word.
Static memory(English) static storage) - a type of memory in which the position of data and their value do not change during storage and reading. A variation of this type of memory is static RAM.
Page memory(English) page memory) - memory divided into identical areas - pages. Exchange with such memory is carried out by pages.
Control memory(English) control storage) - memory containing control programs or microprograms. Typically implemented in the form of ROM.
Different types of memory have different advantages, which is why most modern computers use several types of storage devices at once.
