This article is about the origin and meaning of the terms computer, computer and computer; it reveals classification relationship between terms:computer, computing machine, analogue computing machine (AVM), digital computing machine (TsVM), electronic digital computing machine (ECVM), programmable electronic digital computing machine, universal programmable electronic digital computing machine (PC), personal computer (PC, PC) , stationary personal computer, wearable personal computer, etc .; the article explains the difference between computers and other computers.

Abbreviations

Remembering the reduction and translation, we get:

A computer is an electronic computer,

Computer - computer is a calculator.

In other words, both are calculators. The first term only emphasizes that the calculator is (a) a machine, not a man, and (b) an electronic machine, and not a mechanical one, for example, it is not an adding machine. The second term does not carry such clarifications.

Origin, meaning and juxtaposition

The word computer appeared in the English literary language at the beginning of the 17th century, however, then it meant "a person doing calculations." At the end of the nineteenth century, this word acquired a second meaning "calculating machine", but only in the middle of the XX century the second meaning "calculating machine" supplanted the first. And now computer means in English any computer: analog, digital, hybrid, etc.

The word computer (more precisely, EFM, an electronic calculating machine) appeared in the USSR in the forties of the XX century, that is, at the same time when the word computer in English was assigned the meaning of a calculating machine. However, from the very beginning, the reduction of the computer did not mean any machine, but an electronic one.

In those years, the "iron curtain" divided not only states, but also the lexicons of peoples, therefore, until the end of the 80s, only the word "computer" was used in Russian, which with different prefixes denoted both "large" computers, and mini- and microcomputers ...

After perestroika, mass deliveries of personal computers (ie, personal computers) began in the USSR; Along with the deliveries, the word “computer” took root in the Russian language. Therefore, in our everyday life - but not in science and technology - "computer" means only "personal computer". Unlike everyday language, in modern scientific, legal and technical Russian, a computer and a computer are one and the same.

A computer and a computer is a calculating machine, which differs from other calculators:

Discrete (digital) computing units, not analog;

Electronic (not mechanical) device of computing units;

Automatic data processing according to a given program;

Versatility of appointment;

Change of programs.

Discreteness of the calculator means that operands in computational operations are numbers, which naturally consist of digits, therefore the second name of a discrete calculator is "digital".

The electronic device of computing units implies that the main arithmetic and logical units of the calculator consist of electronic components (vacuum tubes, transistors, microcircuits, etc.). In particular, a computer based on a relay, that is, based on electrical and not electronic components, made by Konrad Zuse in 1941, today is not called a computer in Russian, but in the English sentence it is referred to as a computer.

Automatic data processing implies non-human intervention in the processing until it is completed. It goes without saying that the processing is quite "long", that is, it consists of several operations, otherwise it makes no sense to arrange automatic processing. Switching from one operation to the next is controlled by software, not human.

The universality of appointment is understood in each era in its own way, in accordance with human imagination and the possibilities of technical means. In the forties, the versatility of the computer consisted in the fact that the result of the work of its programs was a variety of mathematical calculations: ballistic, aerodynamic, etc. processes. In the seventies, in addition to the already mentioned, - to plan transportation, reserve tickets for transport, forward e-mail; in the eighties - to show pictures, to help design buildings, electronic devices, and in the nineties - to play and entertain.

Today, universal computer programs should, as before, be able to do any calculations, carry out numerical modeling of physical processes, decode DNA, process pictures, geographical maps, texts, show movies, play music, etc. All the just listed program capabilities are external manifestations of internal computer abilities. It goes without saying that external manifestations are based on the internal abilities of algebraic, arithmetic and logical blocks, which remain exclusively computational. The computer simply does not have other internal abilities.

A non-universal, specialized computer and its programs can do one thing: either process pictures, or plot a route along a geographic map, or show a movie. A specialized computer is called a controller. Controllers, not computers, are computers built into communicators, navigators, video recorders, washing machines and other household appliances. Controllers built into moving mechanisms (airplanes, cars, tanks) are called onboard controllers.

Changing programs in a computer means that its owner, and not the manufacturer, can easily choose for execution any of the programs installed on the computer or install a new program that appeared even later than this computer was released.

Classification relations

The ancestors of all computers can be considered computers, which are of three types: analog, discrete or digital, hybrid. Digital computers can be mechanical (adding machine), electrical (Konrad Zuse's machine on a relay), electronic. The latter are called computers or computers. Once again, it should be noted that in English the word computer refers to any computing machine.

The classification scheme (Figure 1) shows quite fully that branch of computers, which leads from computers to computers and their varieties. Other classification branches are incomplete. The diagram also shows the location of several English concepts.

In the diagram, only the computer branch is fully shown (and highlighted in color).

Figure 1 - Computer = computer = kind of computers

This diagram is intended to show first and foremost:

The place of computers in the family of computers;

Classification equivalence of the terms "computer" and "computer";

The division of personal computers into two types: stationary (for example, desktop) and wearable (for example, laptops and tablets).

It is possible that after the appearance and mass distribution of optical or biological computers, the term "computer" will become much broader in meaning than the term "electronic computer". It is possible that then the term "optical computing machine, OBM" or, rather, "optical computer" will appear. Then the classification scheme will change.

By the way, derivative concepts: PC ("personal computer") and "personal computer" converged in the Russian everyday language much closer to each other than the original ones.

The words “computer” and “computer” cannot be opposed. In modern Russian, in scientific, legal and technical terms, they mean the same thing.

When in everyday life they say "computer", they often mean "personal computer" only because they are not very familiar with other computers.

The word "computer" is gradually replacing the word "computer". It is possible that soon the term "computer" will mean not only electronic (perhaps not electronic at all), but the optical or biological basis of a computer, that is, it will become much broader in meaning than the term "electronic computer". Then the concepts of a computer and a computer will diverge in meanings.

1 The Iron Curtain, however, was of some use. Isolation forced translators transfer foreign language terms into Russian, and not just try to pronounce them in the Russian way. For example, I recently discovered a translation of the word gadget in a scientific book from the 60s; it sounded like a gizmo. 2 This concept justifies a certain eclecticity of the scheme, which resulted from the confusion of several classification features. 1 ... Wikipedia. http://en.wikipedia.org/wiki/Computer .

What is a computer?

Computer (English computer - calculator) - a programmable electronic computing device for data processing, transmission and storage of information. That is, a computer is a complex of software-controlled electronic devices.

The term " computer" (or " Personal Computer") Is synonymous with the abbreviation" computer"(Electronic computer) or" PC "(personal computer). After the appearance of personal computers (from the English personal computer, PC), the term "computer" was subsequently practically supplanted from use and replaced by the borrowed term "computer", "PC" or "PC". The fact is that if the designations "PC" and "PC" characterize a computer as a "single-user universal computer", then the term "PC" means exactly an IBM PC-compatible computer.

With the help of calculations, a computer is able to process information according to a predetermined algorithm. In addition, a computer with the help of software is able to receive, store and search for information, display information on various types of output devices. Computers got their name from their main function - carrying out calculations. Currently, in addition to the direct functions of computing, computers are used to process and manage information, as well as games.

The scheme of a computer was proposed by the famous mathematician John von Neumann in 1946; its principles of operation are largely preserved in modern computers.

First of all, a computer, according to the principles of von Neumann, must have the following devices:

* arithmetic logic unit (ALU) that performs arithmetic and logical operations;
* control device (UU), which organizes the process of executing programs;
* storage device (memory), or memory for storing programs and data;
* external devices for input-output of information.

Computer memory must consist of a number of numbered cells, each of which can contain either processed data or program instructions. All memory cells should be equally easily accessible to other computer devices.

In addition to the computer architecture, Neumann proposed the fundamental principles of the logical device of a computer.

John von Neumann's principles:

1. The principle of programmed control (the program consists of a set of commands that are executed by the processor one after another in a certain sequence);

2. The principle of memory homogeneity (programs and data are stored in the same memory);

3. The principle of addressing (the main memory consists of numbered cells, and any cell is available to the processor at any time).

Computers built on these principles are classified as "von Neumann". Today these are the overwhelming majority of computers, including IBM PC-compatible ones. But there are also computer systems with a different architecture - for example, systems for parallel computing.

Typically, a computer is designed based on the principle of open architecture:
* Description of the principle of operation of the PC and its configuration, which allows you to assemble a PC from individual assemblies and parts;
* Availability of internal expansion slots in the PC, into which the user can insert various devices that meet the specified standard.

In most modern computers, the problem is first described in a form that they understand, while all the necessary information is presented in binary form (in the form of ones and zeros), after which the steps for processing it are reduced to the application of simple algebra of logic. Since almost all mathematics can be reduced to performing Boolean operations, a sufficiently fast electronic computer can be used to solve most mathematical problems (as well as most information processing problems that can be easily reduced to mathematical ones).

The result of the completed task can be presented to the user using various information output devices, such as lamp indicators, monitors, printers, projectors, etc.

It was discovered that computers still cannot solve any mathematical problem. For the first time, problems that cannot be solved by computers were described by the English mathematician Alan Turing.

Application of computers

The first computers were created directly for computing (which is reflected in the names "computer" and "computer"). It is no coincidence that the first high-level programming language was Fortran, designed exclusively for performing mathematical calculations.

The second major application was databases. First of all, they were needed by governments and banks. Databases require more sophisticated computers with advanced input-output and information storage systems. For these purposes, the Cobol language was developed. Later, DBMS (database management systems) appeared with their own programming languages.

The third application was the control of all kinds of devices. Here, the development went from highly specialized devices (often analog) to the gradual introduction of standard computer systems on which control programs are run. In addition, more and more technology begins to include a control computer.

Finally, computers have evolved so much that the computer has become the main information tool in the office and at home. That is, now almost any work with information is carried out through a computer - be it typing or watching movies. This also applies to the storage of information, and to its transfer through communication channels.

Modern supercomputers are used to simulate complex physical and biological processes, such as nuclear reactions or climate change. Some projects are carried out using distributed computing, where a large number of relatively weak computers simultaneously work on small parts of a common problem, thus forming a very powerful computer.

The most complex and underdeveloped application of computers is artificial intelligence - the use of computers to solve problems where there is no clearly defined more or less simple algorithm. Examples of such tasks are games, machine translation of text, expert systems.

GENERAL INFORMATION ABOUT COMPUTERS AND COMPUTER SYSTEMS

Parameter name	Meaning
Topic of the article:	GENERAL INFORMATION ABOUT COMPUTERS AND COMPUTER SYSTEMS
Category (thematic category)	Computers

To process information, electronic computers (computers), computer systems (CS) and computer networks are used.

Computer - ϶ᴛᴏ an electronic device for the accumulation and automatic processing of information.

The main functional blocks of the computer:

1) input device (UVV);

2) storage device (memory);

3) arithmetic logic unit (ALU);

4) control unit (UU);

5) output device (UVv).

To solve the problem, compiled program, ᴛ.ᴇ. a sequence of commands written in a language understandable by a computer. Recorded on a machine medium (for example, a magnetic disk), programs and data are entered into a computer through the IWC and transferred to a memory device (computer memory).

The largest number of commands and data that can be simultaneously stored in the memory determines memory capacity... The time ĸᴏᴛᴏᴩᴏᴇ required to search, write and read information determines computer speed.

The memory must include operational (RAM) and read-only (ROM) storage devices that make up internal memory.

External memory The computer is designed to store intermediate results that do not fit in RAM, input and output data. External memory is practically unlimited, but its speed is significantly less than RAM.

To organize the interaction between the computer devices during the execution of the program, the control unit is used. At the instruction of the UU, the next command is entered and decrypted, an indication is transmitted to the memory, which data to transfer to the ALU and what operation to perform. The intermediate results are sent to storage in RAM. In the ALU, arithmetic and logical operations are performed on the data. The results of the work are transmitted to the UVv. Since the same devices can be used for both input and output, they are called input-output devices (IO).

Control unit, arithmetic logic unit and high-speed register memory (cache memory) make up CPU(CPU). In a PC, its functions are performed by a microprocessor.

Computing systems- a set of computer technology, which includes at least two basic processors or computers (universal or specialized) and a developed system of peripheral devices.

Peripherals- ϶ᴛᴏ external storage devices and input-output devices.

PERSONAL COMPUTER(PC) or PC - universal single user computer(at niversal- since it can be used to solve problems of different types, and single user- since one user can work at a time). From the name it is clear that such a computer is designed to serve one workplace.

The configuration (equipment composition) of the PC can be flexibly changed at the utmost importance. With all the variety of computers in any computer, the following components can be distinguished:

· system unit;

· Display for visual display of information;

· Keyboard for entering symbolic information;

· Mouse (or other pointing device);

· peripherals.

The first four components are basic configuration, which can be expanded with additional external devices.

The system unit houses the main components of the PC (called internal), the most important of which is the motherboard (system). It contains a basic set of PC electronics (CPU, electronic devices (chipsets) and others).

All are connected to the system unit external devices: monitor, keyboard, mouse, printer, modem, scanner, speakers, etc.

The SYSTEM UNIT contains the following devices.

1. Motherboard on which the following devices are located.

· Microprocessor (MP). This is the main PC chip that performs most of the logic and math operations. Structurally, the processor consists of an array of crystal cells in which data can be stored and changed. The internal cells of the processor are called registers. With the rest of the computer's devices, and primarily with RAM, the processor is connected by several groups of conductors called tires... There are three main buses: data bus, address bus and command bus.

Address bus for Intel Pentium processors, it is 32-bit, that is, it consists of 32 parallel lines, on which one or zero is set based on whether there is a voltage on the line or not. The combination of 32 zeros and ones forms a 32-bit address that points to one of the cells in RAM. A processor is connected to it to copy data from a cell to one of its registers.

By data bus data is copied from RAM to processor registers and vice versa. In computers with an Intel Pentium processor, the data bus is 64-bit, that is, it consists of 64 lines, along which 8 bytes are processed at once for processing.

Command bus is designed to transfer commands to the processor from those areas of RAM where programs (and not data arrays) are stored, since in order for the processor to process data, it needs instructions. Commands are represented as bytes. The Intel Pentium processor has a 32-bit instruction bus.

Modern processors perform hundreds of millions of operations per second, allowing PCs to solve highly complex tasks in short periods of time.

The processor is responsible for the performance characteristics of the PC. Microprocessors differ in a number of important characteristics: processor capacity, clock frequency of information processing.

Processor size shows how many bits of data it can receive and process in its registers in one clock cycle. The first processors were 16-bit, starting with the 80386 - 32-bit.

Information processing clock frequency... All processes related to calculations, processing and transfer of data between PC modules must be mutually consistent in time, ᴛ.ᴇ. synchronized. Synchronization of the CPU and all PC nodes is carried out using a clock generator, which generates periodic sequences of clock pulses. Tact is called the time interval between the beginning of the supply of two successive pulses of electric current, which are produced by the clock generator.
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A sequence of clock pulses is sent to the CPU, to the memory system, to all other devices in the computer to synchronize the operation of the CPU and all the nodes of the computer. Clock frequency- ϶ᴛᴏ number of ticks per second and is measured in megahertz(1 MHz = 1 million cycles per second), affects the speed of work, the speed of the MP.

Processor speed- ϶ᴛᴏ the number of operations performed by it per second. Performs hundreds of different operations at a speed of hundreds of millions of operations per second.

The PC uses microprocessors developed by Intel, AMD and others. Today, INTEL 80486 microprocessors are being replaced by more powerful Pentium microprocessors (Pentium 3, Pentium 4 with frequencies of 500 megahertz and higher.

· Video adapter (video card)- ϶ᴛᴏ a device that controls the display of text information and graphic images. The video adapter organizes the interface between the PC and the display. Physically, the video adapter is made in the form of a separate board, which is inserted into one of the slots on the motherboard.

Today, SVGA video adapters are used, which provide an optional reproduction of up to 16.7 million colors with a choice of screen resolution from a number of values ​​(for example, 1024 * 768 pixels for 17-inch monitors).

· RAM- ϶ᴛᴏ array of crystal cells capable of storing data. Serves for writing and reading information. When the power is turned off, the information stored in the memory will be lost. It is characterized by a speed comparable to that of a microprocessor.

The main characteristics of RAM are capacity and access time. Capacity modern RAM is several GB. Access time shows how much time is extremely important for accessing memory cells, measured in billionths of a second (nanoseconds, ns). It is important to note that for modern memory modules it is 7-10 ns.

· ROM- intended for storing short programs necessary for the functioning of the PC.

At the moment the computer is turned on, there is nothing in its RAM - neither data nor programs, since RAM cannot store anything without recharging the cells for more than hundredths of a second, but the processor needs commands, incl. and at the first moment of switching on. For this reason, immediately after switching on, the start address is set on the processor's address bus (this happens in hardware, without the participation of programs). The processor addresses the set address for its first command and then begins to work according to programs. This address points to the ROM. The ROM chip is capable of storing information even when the computer is turned off. The complex of programs located in ROM forms basic input / output system... The main purpose of the programs in this package is to check the composition and operability of a computer system and to ensure the interaction of all its components.

· Cache memory- it is also called speed memoryʼʼ.

The exchange of data inside the processor is several times faster than the exchange with other devices, for example, with RAM. In order to reduce the number of calls to RAM, a buffer area is created inside the processor - the so-called cache memory... When the processor needs data, it first accesses the cache memory, and only if there is no necessary data there, it is called into the RAM. Receiving a block of data from RAM, the processor writes it simultaneously to the cache memory. The cache is functionally designed to match the speed of relatively slow devices with a relatively fast CPU. Compared to the RAM, the cache memory has a small capacity. In addition to the built-in CPU, the cache memory must be removed from the CPU. On-board cache is the fastest; L1 cache is typically 32KB in size.

· Chipset- ϶ᴛᴏ a set of microcircuits designed to support in a PC the functionality provided by a processor, RAM, cache memory, disk and video memory and other components and to integrate the component parts of a PC. Its microcircuits generate most of the signals for system and peripheral components, convert signals between buses.

· Controllers are designed to control access from the system to any of the devices, as well as to perform information exchange operations. Each external device has its own controller.
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After receiving commands from the CPU, the controller performs maintenance operations on the external device. Controllers built on the motherboard (keyboard controllers, HDD, HDD, ports, video systems) are widely used.

2. Disk drive (drive) for floppy magnetic disks (floppy disk drive). For the online transfer of small amounts of data, use floppy disks(floppy disks) that are inserted into a special drive - drive... The correct direction of feeding the floppy disk into the drive hole located on the front panel of the system unit is marked with an arrow on its plastic casing.

The disk drive is used to write, read and store information on floppy disks (floppy disks). Nowadays, floppy disks with a diameter of 3.5 "with a capacity of 1440 bytes ( 1.4 Mb) and HD marking.

Floppy disks are unreliable media. Dust, dirt, moisture, temperature extremes and external electromagnetic fields often cause partial or complete loss of information. For this reason, it is unacceptable to use them as the main storage medium. They are used to transport data or as an additional (backup) storage medium.

3. Hard disk drive (HDD) or Winchester. Designed for long-term storage (it can store information for tens of years).

A hard drive is not really a single drive, but a group of magnetically coated coaxial drives that spin at high speed. Τᴀᴋᴎᴍ ᴏϬᴩᴀᴈᴏᴍ, the hard drive does not have two surfaces, but 2n surfaces, where n is the number of individual disks in the group.

Capacity hard drives today - from a few GB to several tens of GB.

4. CD-ROM drive... Digital CD recording differs from magnetic disc recording at a very high density, and a standard CD can store approximately 650 MB of data. Οʜᴎ are distinguished by high reliability of information storage, durability (the predicted service life with high-quality performance is 30-50 years). The diameter of the disc should be both 5.25 "and 3.5".

The principle of operation of this device is reading numerical data using a laser beam reflected from the surface of the disk. Large amounts of data are typical for multimedia information (graphics, music, video), therefore CD-ROM drives are classified as hardware multimedia.

5. Tires. All electronic elements of a PC exchange information with each other and are interconnected using buses - a set of lines and microcircuits that transmit electrical signals between various PC components. The collection of all buses is commonly referred to as the system backbone. The buses transmit signals: address, control and data, in this regard, a distinction is made between: data bus (for data transmission), address bus (for transferring address information codes to RAM) and control bus (includes lines for transmitting control signals).

Tires are characterized by bitness, ᴛ.ᴇ. the number of bits of information simultaneously transmitted over the bus lines. In PC architecture, 8-, 16-, and 32-bit buses are most common. The amount of information transmitted over the channel in 1 time is usually called bus bandwidth.

6. Communication ports (I / O ports)... Serve for communication of a personal computer with devices that are structurally made separately from the system unit. Specialized ports are used for exchange with internal devices. Ports general purpose used to connect external devices: parallel LPT1-LPT * and serial COM1-COM *.

MONITOR ( display) - a device for visual presentation of data. This is the main output device. Serves for the output of text and graphic information entered from the keyboard or output from the PC data, system messages and user information.

Screen size measured diagonally between opposite corners of the kinescope screen in inches. Today, 19 "and 21" monitors are widely used.

Permission screen is one of the important parameters of the monitor. The higher it is, the more information can be displayed on the screen, but the smaller the size of each individual point, and hence the smaller the visible size of the image elements.

The display and video card (graphics card) make up video system PC. Video systems use analog and digital technology to obtain a display on the screen. In analog technologies, displays on cathode ray tubes are used, in digital technologies, liquid crystal flat screen displays are used.

The KEYBOARD is used to enter alphanumeric data and control commands into the PC. The main functions of the keyboard do not need to be supported by drivers (special programs). The necessary software to start working with the computer is already included in the ROM chip in the BIOS.

The MOUSE allows you to point to screen elements with the pointer and, after clicking the buttons, perform certain operations.

The PRINTER displays text and graphic information (black and white or color) on paper or film.

MODEM is used to connect a PC to a telephone line.

SCANNER is a device for entering text or graphic information (black and white and color) into a PC for its further processing.

SOUND SYSTEM consists of a sound card and sound speakers (they are built into the display). The speakers have their own amplifiers and sound level controls.

The most promising is the use of a personal computer as part of a computer network (BC). In this case, several PCs, and, possibly, computers of other classes, are connected together by means of communication channels and equipment for interfacing with them for information exchange.

Computer network it is customary to call a set of PCs interconnected through data transmission channels, which provide users with the exchange of information and the sharing of network resources.

Network hardware:

- workstations(workstation - ϶ᴛᴏ a PC connected to the network on which the network user performs his work);

- server(a computer connected to a network and providing certain general purpose services to network users);

- network cards(adapters);

- modems;

- cables or other transmission media.

By degree of territorial distribution networks are classified into: global, regional and local networks.

Global networks unite users located all over the world, often use satellite communication channels (the distance between network nodes is 10-15 thousand km). They are called WAN.

Regional- unite users of the city, region. Telephony lines are used as communication channels (the distance between network nodes is 10-1000 km). They are called MAN.

Local networks connect subscribers of one or more nearby buildings. PCs are connected by a single high-speed data transmission channel. Distances between computers are small - up to 10 km. Channels in local networks are the property of organizations, and this simplifies their operation.

Networks consisting of software-compatible computers are called homogeneous... If a software incompatible computer is included in the network, then the network is usually called heterogeneous.

The use of local area networks provides the following advantages:

· Simultaneous work of several users with data of general use (DBMS, ET);

· Data protection at the level of directories and files;

· The ability to permanently store software required by many users in one copy;

· Exchange of information between all PCs in the network, thus providing a dialogue between network users, as well as the possibility of organizing the work of e-mail;

· Simultaneous printing by all network users on network-wide printers;

· Increasing the efficiency of information processing systems by reducing costs, etc.

A global network capable of uniting many networks and allowing entry into the world community is Internet.

Today there is no single owner of the Internet. Each company is the master of its part of the network. It also possesses the necessary software and hardware, with the help of which data is exchanged both within its own network and within the Internet. This company also provides transit information through its network. In case of failures in a certain section of the network, all information will "flow" over this section.

Internet connection methods

· Connection of an individual PC. To do this, you need to have a modem, telephone line and an organization that has a gateway (entrance) to the Internet. Such organizations - network service providers - are called providers... Access to the Internet is carried out through the provider's PC. This PC is usually called host... The user works on the network without having an address. It is contained by the host PC. All information that the user downloads goes through the host.

· Direct connection... Direct connection to the Internet is carried out via dedicated leased communication lines using additional software.

An analysis of the practice of using the aircraft showed that there are many ways of information leakage: illegal connection to equipment and communication lines, interception of electronic emissions, interception of acoustic emissions and restoration of printer text, theft of information carriers, reading data from other users' arrays, reading residual information in the system memory after the execution of an authorized request, disguise as a registered user, the introduction of viruses, etc.
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In this regard, information protection measures are of particular importance:

Organizational (restricting access to the room where information is processed; storing machine media in safes; using security codes when transferring information, etc.);

Technical and software.

GENERAL INFORMATION ABOUT COMPUTERS AND COMPUTER SYSTEMS - concept and types. Classification and features of the category "GENERAL INFORMATION ABOUT COMPUTERS AND COMPUTER SYSTEMS" 2017, 2018.

Basic terms, definitions and concepts of computers.

Computer (computer)- a device capable of executing a well-defined sequence of operations prescribed by a program.

Personal computer (PC) usually focused on interactive interaction with 1 user, and interaction occurs through a variety of communication media - from alphanumeric and graphical dialogue using a display, keyboard and mouse to virtual reality devices.

When the abbreviation PC (Personal Computer) is used, it means a PC compatible with the mainstream family of IBM PCs and their clones. The PC can also be used collectively: the capabilities of many computers of this family allow them to be used as servers in local networks. Collocation PC server suggests increased power(speed of calculations, the amount of RAM and external memory) and a special design (spacious case) of the computer.

File Server is the core of the local network. This computer (usually a high-performance minicomputer) runs the OS and controls the data flow over the network. Individual workstations and any shared peripherals such as printers are all connected to the file server.

Work station- is a normal PC running its own OS. However, unlike a stand-alone PC, a workstation contains a network interface card and is physically cabled to a file server. Also, the slave. the station launches a special program (network shell) that allows it to exchange information with the file server, other workstations and other network devices. The shell allows a workstation to use files and programs stored on a file server as easily as those on its own disks.

Super-computer- Computers with the highest productivity, and mainly intended for solving complex scientific and technical problems.

General purpose computer- computers designed to solve a wide class of problems with approximately the same technical and economic efficiency.

Mini-computer- computers, developed from the requirement to minimize cost and designed to solve fairly simple problems.

Microcomputer- computers, the central part of which is built on one or more microprocessors and developed based on the requirement to minimize the physical volume.

Specialized computer- a computer that has functionality and design features that allow it to be used to effectively solve a limited class of problems in certain environmental conditions.

OS- a set of systems. programs designed to ensure a certain level of efficiency of the information processing system due to the automated control of its operation and a certain set of services provided to the user.

CPU- a functional part of a computer or information processing system, designed to interpret programs.

Central processing unit (CPU)- the processor performing in this subclause. machine or information processing system, the main functions of information processing and control of the work of other parts of the comp. machines or systems.

Architecture- these are the most general principles of building a computer that implement program control of the work and interaction of its main functional units.

The main characteristics of the computer.

1) cost / performance ratio 2) reliability 3) fault tolerance 3) speed 5) memory size 6) computational accuracy 7) instruction set 8) scalability; 9) software compatibility 10) software mobility.

Computer performance is determined by the number of operations performed by the processors per unit of time, as well as the amount of memory available in the machine and used for storing and processing information.

Computer cost depends on a large number of factors: speed, memory capacity, instruction set, etc. The main influence on the cost is exerted by a specific computer configuration and, in the main, external devices that make up the final composition of the machine. Also, software has a rather significant effect on the cost of a computer.

Computer reliability- the ability of a computer to maintain its properties under specified operating conditions for a certain period of time.

fault tolerance- a property of a computing system, which provides it, as a logical machine, the ability to continue the actions specified by the program, after the occurrence of malfunctions. The introduction of fault tolerance requires redundant hardware and software. Areas related to fault prevention and fault tolerance are central to the problem of reliability.

Computer speed viewed from both sides. On the one hand, it is characterized by the number of elementary operations (any simple operation such as addition, transfer, shift, etc.) performed by the processor per second. On the other hand, the speed of a computer essentially depends on how its memory is organized. The time required to search for the necessary information in memory significantly affects the speed of the computer.

Capacity, or Memory is determined by the limiting amount of information that can be placed in the computer memory. Computer memory is divided into internal and external. Internal, or random access memory, in its volume for different types of machines is different and is determined by the computer addressing system. External storage capacity is virtually limitless thanks to the block structure and removable drive designs.

Calculation accuracy depends on the number of digits used to represent one number. Modern computers are equipped with 32- or 64-bit microprocessors, which is sufficient to ensure very high accuracy of calculations in a wide variety of applications. However, if this is not enough, you can use a doubled or tripled grid of discharges.

Command system is a list of commands that the computer processor is capable of executing. The instruction set determines what operations the processor can perform, how many operands must be specified in the instruction, what kind (format) the instruction has for its recognition.

Scalability- the ability to increase the number and capacity of processors, the amount of RAM and external memory and other resources of the computing system. Scalability must be ensured by the architecture and design of the computer, as well as the appropriate software tools.

Software compatibility concept- the ability to run the same programs on different computers with the same results.

Software mobility- the ability to run the same software systems on different hardware platforms.

Open System Environment Model - IEEE POSIX Committee.

Municipal budgetary educational institution

"Secondary school number 30"

Performed:

Pupil of grade 8 A

Dmitrieva Daria

Teacher:

Demchenko E.E.

Kursk, 2014

"History of the development of computer technology"

abstract

Introduction

Human society, in the course of its development, has mastered not only matter and energy, but also information. With the advent and widespread distribution of computers, a person received a powerful tool for the effective use of information resources, for enhancing his intellectual activity. From now on (middleXXcentury), the transition from an industrial society to an information society began, in which information becomes the main resource.

The ability of members of society to use complete, timely and reliable information largely depends on the degree of development and assimilation of new information technologies, which are based on computers. Let's consider the main milestones in the history of their development.

Computer Engineering is an essential component of the process of computing and data processing. The first devices for computing were probably the well-knowncounting sticks, which are still used today in the elementary grades of many schools to teach counting. As these adaptations evolved, they became more complex, for example, such asPhoenicianclay figurines, also designed to visually represent the number of items counted. Such devices seem to be used by traders and bookkeepers of the time.

Gradually, more and more complex devices were born from the simplest devices for counting.: ( ), , , ... Despite the simplicity of early computing devices, an experienced bookkeeper can get results with simple counting even faster than the slow-moving owner of a modern calculator. Naturally, the productivity and counting speed of modern computing devices have long surpassed the capabilities of the most outstanding human calculator.

Humanity has learned to use the simplest calculating devices thousands of years ago. The most popular was the need to determine the number of items used in exchange trade. One of the simplest solutions was to use the weight equivalent of a variable item, which did not require an exact recalculation of the number of its components. For these purposes, we used the simplest balancingbalance, which was one of the first devices for quantificationmasses. The principle of equivalence was widely used in another simple calculating device - the abacus, or abacus. The number of objects to be counted corresponded to the number of knuckles of this instrument moved. A relatively complex device for counting could be the rosary used in the practice of many religions. The believer, as if on counts, counted out the number of prayers on the rosary beads, and when passing a full circle of the rosary, he moved special grain-counters on a separate tail, meaning the number of counted circles.With the invention of gears, much more sophisticated computing devices appeared.

About all generations of computers,about the history of the development of computer technology, I want to tell in my essay.

The beginning of the computer era

The first computerENIACwas created at the end of 1945 in the United States.

The main ideas on which computing technology developed for many years were formulated in 1946 by the American mathematician John von Neumann. They are called von Neumann architecture.

In 1949, the first computer with the von Neumann architecture was built - an English machineEDSAC... A year later, an American computer appearedEDVAC.

In our country, the first computer was created in 1951. It was called MESM - a small electronic calculating machine. The designer of the MESM was Sergei Alekseevich Lebedev.

Serial production of computers began in the 50sXXcentury.

Electronic computing technology is usually divided into generations associated with the change of the element base. Moreover,cars of different generations are differentlogical architecture and softwareprovision, quicklyaction, RAM, input method and youinformation water, etc.

The first computer - a universal machine based on electronic tubes - was built in the USA in 1945.

This machine was called ENIAC (stands for electronic digital integrator and computer). The designers of ENIAC were J. Mauchly and J. Eckert. The counting speed of this machine exceeded the speed of the relay machines of that time a thousand times.

First electroniccomputer ENIAC was programmed using the plug-and-switch method, that is, the program was built by connecting individual blocks of the machine with conductors on the switch board. This complex and tedious procedure for preparing the machine for work made it inconvenient to operate.

The main ideas on which computing technology developed for many years were developed by the largest American mathematician John von Neumann.

In 1946, the journal "Nature" published an article by J. von Neumann, G. Goldstein and A. Burks "Preliminary consideration of the logical design of an electronic computing device." In this article, the principles of the structure and operation of a computer were outlined. The main one is the principle of stored in memoryprograms , according to which the data and the program are placed in the shared memory of the machine.

The fundamental description of the structure and operation of a computer is usually called a computer architecture. The ideas presented in the above-mentioned article were called "architecture of the computer by J. von Neumann".

In 1949, the first computer with the Neumann architecture was built - the English machine EDSAC. A year later, the American EDVAC computer appeared. The named machines existed in single copies. Serial production of computers began in the developed countries of the world in the 50s of the XX century.

In our country, the first computer was created in 1951. It was called MESM - a small electronic calculating machine. The designer of MESM was Sergey Alekseevich Lebedev

The role of Academician S. A. Lebedev in the creation of domestic computers is great. Under his leadership, in the 50s, serial lamp computers BESM-1 (high-speed electronic calculating machine), BESM-2, M-20 were built. At the time, these machines were some of the best in the world.

In the 60s of the XX century, S. A. Lebedev led the development of semiconductor computers BESM-ZM, BESM-4, M-220, M-222. An outstanding achievement of that period was the BESM-6 machine. This is the first domestic and one of the first computers in the world with a speed of 1 million operations per second.

Subsequent ideas and developments of S. A. Lebedev contributed to the creation of more advanced machines of the next generations.

The first generation of computers

The first generation of computers - tube machines of the 50s.The counting speed of the fastest machines of the first generation reached 20 thousand operations per second. Punched tapes and punched cards were used to enter programs and data. Since the internal memory of these machines was small (it could accommodate several thousand numbers and program instructions), they were mainly used for engineering and scientific calculations not related to the processing of large amounts of data. These were rather bulky structures, containing thousands of lamps, sometimes occupying hundreds of square meters, and consuming hundreds of kilowatts of electricity. Programs for such machines were compiled in machine instruction languages, so programming in those days was available to few. It is generally accepted that the first generation of computers appeared during the Second World War after1943 Konrad Zuse, shown to friends and relatives in1938 relay) machine, capricious in handling and unreliable in calculations. In May1941 years inBerlin

It is generally accepted that the first generation of computers appeared during the Second World War after1943 years, although the first working representative should be considered a V-1 (Z1)Konrad Zuseshown to friends and family members in1938 year. It was the first electronic (built on homemade analogsrelay) a machine, capricious in handling and unreliable in calculations. In May1941 years inBerlin, Zuse presented the Z3, which delighted specialists. Despite a number of shortcomings, it was the first computer that, under other circumstances, could have been a commercial success.

However, the first computers are considered EnglishColossus(1943) and AmericanENIAC(1945). ENIAC was the first vacuum tube computer.

Computers of the first generation used electronic tubes and relays as an element base; RAM was performed on triggers, later on ferrite cores.The element base of the first computers - electronic tubes - determined their large dimensions, significant energy consumption, low reliability and, as a result, small production volumes and a narrow circle of users, mainly from the world of science. In such machines, there were practically no means of combining the operations of the program being executed and parallelizing the operation of various devices; commands were executed one after another, the ALU was idle in the process of data exchange with external devices, the set of which was very limited. The volume of the BESM-2 RAM, for example, was 2048 39-bit words; magnetic drums and magnetic tape drives were used as external memory. The process of human communication with the first generation machine was very laborious and ineffective. As a rule, the developer himself, who wrote the program in machine codes, entered it into the computer memory using punched cards and then manually controlled its execution. For a certain period of time, an electronic monster was given to the programmer for undivided use, and the efficiency of solving a computational problem largely depended on the level of his skill, the ability to quickly find and correct errors and the ability to navigate at the computer console. The focus on manual control determined the absence of any program buffering capabilities.

Computers of the first generation were not very reliable, required a cooling system and had significant dimensions. The programming process required significant art, good knowledge of computer architecture and its software capabilities. First, programming in computer codes (machine code) was used, then autocodes and assemblers appeared, to a certain extent automating the process of programming tasks. Computers of the first generation were used for scientific and technical calculations. The programming process was more like an art that was practiced by a very narrow circle of mathematicians, electronics and physicists.

All computers of the 1st generationfunctionedbased on vacuum tubes, which made them unreliable - the tubes had to be changed frequently. These computers were huge, inconvenient, and too expensive machines that only large corporations and governments could buy. The lamps consumed a huge amount of electricity and generated a lot of heat.

Moreover, each machine used its own programming language. The set of commands was small, the circuit of the arithmetic logic unit and the control unit was quite simple, and there was practically no software. The indicators of the amount of RAM and performance were low. For input-output, punched tapes, punched cards, magnetic tapes and printing devices were used, random access memory devices were implemented on the basis of mercury delay lines of cathode ray tubes.

These inconveniences began to be overcome by intensive development of programming automation tools, creation of systems of service programs that simplify the work on the machine and increase the efficiency of its use. This, in turn, required significant changes in the structure of computers, aimed at bringing it closer to the requirements arising from the experience of operating computers.

Second generation computer

In 1949, the first semiconductor device was created in the United States to replace the electronic lamp. It is called the transistor.In the 60s transistors have become an element base for Second generation computer... The transition to semiconductor elements improved the quality of computers in all respects: they became more compact, more reliable, and less energy-intensive. The performance of most machines has reached tens and hundreds of thousands of operations per second. The volume of internal memory has increased hundreds of times compared to the first generation computers. External (magnetic) memory devices have been greatly developed: magnetic drums, magnetic tape drives. Thanks to this, it became possible to create information and reference and search systems on computers (this is due to the need to store large volumes of information on magnetic media for a long time).During the second generation, high-level programming languages ​​began to develop actively. The first of them were FORTRAN, ALGOL, COBOL. Programming as an element of literacy has become widespread, mainly among people with higher education.

The second generation of computers is a transition to a transistor element base, the appearance of the first mini-computers.

Second generation computers usually consisted of a large number of printed circuit boards, each containing from one to fourlogic gatesortriggers. In particular,IBM Standard Modular Systemdefined the standard for such boards and connection connectors for them. V1959 yearbased on transistors IBM released mainframeIBM 7090and a middle class carIBM 1401. The last usedpunch cardinput and became the most popular general-purpose computer of that time: in the period 1960-1964. more than 100 thousand copies of this machine were produced. It used 4,000 character memory (later increased to 16,000 characters). Many aspects of this project were based on the desire to replace the punch card machines that were widely used since1920suntil the very beginning of the 1970s. V1960 yearIBM has released a transistorIBM 1620, originally only punched tape, but soon upgraded to punched cards. The model became popular as a scientific computer, about 2000 copies were produced. The machine used magnetic core memory with a capacity of up to 60,000 decimal digits.

In the same 1960DECreleased its first model -PDP-1 designed for use by technical personnel in laboratories and for research.

V1961 yearBurroughs CorporationreleasedB5000, the first dual-processor computer withvirtual memory. Other unique features werestack architecture,descriptor-based addressing, and no programming directly toassembly language.

Second generation computerThe IBM 1401, produced in the early 1960s, occupied about a third of the global computer market, with more than 10,000 of these machines sold.

The use of semiconductors has improved not onlycentral processing unit, but also peripherals. The second generation of storage devices was capable of storing tens of millions of characters and numbers. A division into rigidly fixed (fixed ) storage devices connected to the processor by a high-speed data link, and removable (removable ) device. Replacing a cassette disc in a removable device took only a few seconds. Although the capacity of removable media was usually lower, but their replaceability made it possible to store an almost unlimited amount of data.Magnetic tapeusually used for archiving data, since it provided more volume at a lower cost.

In many second-generation machines, the functions of communicating with peripheral devices were delegated to specializedcoprocessors. For example, whileperipheral processorperforms reading or punching of punched cards, the main processor performs calculations or branches in the program. One data bus carries data between memory and the processor during an instruction fetch and execute cycle, and usually other data buses serve peripherals. On thePDP-1memory access cycle took 5 microseconds; most of the instructions took 10 microseconds: 5 for an instruction fetch and another 5 for an operand fetch.

"Setun"was the first computer based onternary logic, developed in1958 yearvThe Soviet Union. The first Soviet serial semiconductor computers were"Spring" and "Snow", produced from1964 on1972 year. The peak performance of the Sneg computer was 300,000 operations per second. The machines were made on the basis of transistors with a clock frequency of 5 MHz. A total of 39 computers were produced.

The best domestic computer of the 2nd generation is consideredBESM-6, created in1966 year.

The principle of autonomy is further developed - it is already implemented at the level of individual devices, which is expressed in their modular structure. I / O devices are equipped with their own controllers (called controllers), which freed the central controllers from managing I / O operations.

Improvement and cheapening of computers led to a decrease in the specific cost of computer time and computing resources in the total cost of an automated solution to a data processing problem, at the same time, the cost of developing programs (i.e. programming) almost did not decrease, and in some cases had a tendency to increase. ... Thus, a tendency towards effective programming was outlined, which began to be implemented in the second generation of computers and is being developed to this day.

The development of integrated systems based on libraries of standard programs that have the property of portability, i.e. functioning on computers of different brands. The most frequently used software tools are allocated in the PPP for solving problems of a certain class.

The technology for executing programs on a computer is being improved: special software tools are being created - system software.

The purpose of creating system software is to speed up and simplify the transition of the processor from one task to another. The first batch processing systems appeared that simply automated the launch of one program after another and thereby increased the processor load factor. Batch processing systems were the prototype of modern operating systems, they were the first system programs designed to control the computing process. In the course of the implementation of batch processing systems, a formalized task control language was developed, with the help of which the programmer told the system and the operator what work he wants to do on the computer. A collection of several tasks, usually in the form of a deck of punched cards, is called a task package. This element is still alive: the so-called batch (or command) MS DOS files are nothing more than job packages (the extension in their name bat is an abbreviation of the English word batch, which means batch).

Domestic computers of the second generation include Promin, Minsk, Hrazdan, Mir.

Third generation computer

Third generation computerwas created on a new element base- integrated circuits: on a small plate of semiconductor material, less than 1 cm in area 2 complex electronic circuits were mounted. They were called integrated circuits (ICs). The first ICs contained dozens, then hundreds of elements (transistors, resistances, etc.). When the degree of integration (the number of elements) approached a thousand, they began to be called large integrated circuits - LSI; then there were very large integrated circuits - VLSI. Computers of the third generation began to be produced in the second half of the 60s, when an American companyIBMstarted production of a system of machinesIBM-360. In the Soviet Union, in the 70s, the production of machines of the ES EVM series (Unified Computer System) began. The transition to the third generation is associated with significant changes in the computer architecture. Now you can run several programs at the same time on one machine. This mode of operation is called multi-program (multi-program) mode. The speed of the most powerful computer models has reached several million operations per second. A new type of external storage device - magnetic disks - has appeared on the third generation machines. New types of input-output devices are widely used: displays, plotters. During this period, the scope of computer applications expanded significantly. Databases, the first artificial intelligence systems, computer-aided design (CAD) and control systems (ACS) began to be created. In the 70s, the line of small (mini) computers received a powerful development.

The element base of a computer is a small integrated circuit (MIS), containing hundreds or thousands of transistors on one plate. The operation of these machines was controlled from alphanumeric terminals. High-level languages ​​and Assembler were used for control. Data and programs were entered both from the terminal and from punched cards and punched tapes. The machines were intended for widespread use in various fields of science and technology (making calculations, managing production, moving objects, etc.). Thanks to integrated circuits, it was possible to significantly improve the technical and operational characteristics of computers and sharply reduce the prices of hardware. For example, the machines of the third generation, compared to the machines of the second generation, have a larger amount of RAM, increased performance, increased reliability, and the power consumption, footprint and weight have decreased.

Integrated circuit, chip - "a microelectronic product having a high packing density of electrically connected elements and considered as a single structural whole." (Gorokhov PK Explanatory dictionary of radio electronics. Basic terms. M .: Russian language, 1993). Before the invention of the integrated circuit (in 1958), each component of an electronic circuit was manufactured separately, and then the components were connected by soldering. The advent of integrated circuits changed all technology. At the same time, electronic equipment has become cheaper. The microcircuit is a multi-layered entanglement of hundreds of circuits, so tiny that they cannot be seen with the naked eye. These circuits also contain passive components - resistors that create resistance to electric current, and capacitors that can store a charge. However, the most important components of integrated circuits are transistors - devices that can both amplify voltage and turn it on and off, "speaking" in binary. The third generation is associated with the emergence of a computer with an element base on integrated circuits (IC). In January 1959, D. Kilby created the first integrated circuit, which was a thin germanium plate 1 cm long. than a similar computer of the old model. But the Kilby integrated circuit had a number of significant shortcomings, which were eliminated with the appearance in the same year of R. Noyce's planar integrated circuits. From that moment on, IP technology began its triumphant march, capturing all new sections of modern electronics and, first of all, computer technology.
The first special onboard computers based on IS technology are designed and built for the US military. The new technology ensured greater reliability, manufacturability, and high-speed performance of computer technology while significantly reducing its size. It turned out to be possible to place thousands of logic elements on one square millimeter of an integrated circuit. However, not only the IS technology has determined the emergence of a new generation of computers - computers of the third generation, as a rule, form a series of models that are software compatible from the bottom up and have capabilities that increase from model to model. At the same time, this technology made it possible to implement much more complex logical architectures of computers and their peripheral equipment, which significantly expanded the functional and computing capabilities of computers.

The most important criterion for distinguishing between computers of the second and third generations is a significant development of the computer architecture that meets the requirements of both the problems being solved and the programmers working on them. With the development of the experimental Stretch computers by IBM and Atlas at the University of Manchester, this concept of computer architecture became a reality; it was implemented already on a commercial basis by IBM with the creation of the well-known IBM / 360 series. Operating systems are becoming part of computers, multiprogramming capabilities have appeared; Many tasks of managing memory, input / output devices and other resources began to be taken over by operating systems or directly by the computer hardware.

The first such series, with which it is customary to count the third generation, is the well-known series of models IBM Series / 360 (or briefly IBM / 360), the serial production of which was started in the USA in 1964; and by 1970 the series included 11 models. This series had a great influence on the further development of general-purpose computers in all countries as a reference and standard for many design solutions in the field of computing technology. Other third-generation computers include such models as PDP-8, PDP-11, B3500 and a number of others. In the USSR and other CMEA countries, in 1972, the production of a Unified Computer Series (ES EVM) began, copying (as far as technologically possible) the IBM / 360 series. Along with the ES EVM series in the CMEA countries and the USSR, in 1970, the production of a series of small computers (SM ECM), compatible with the well-known PDP series, was started.

If the models of the IBM / 360 series did not fully use the IS technology (methods of miniaturization of discrete transistor elements were also used), then the new IBM / 370 series was already implemented using 100% IS technology, retained continuity with the 360 ​​series, but its the models had significantly better technical characteristics, a more developed command system and a number of important architectural innovations.

The software that ensures the functioning of computers in various operating modes is becoming much more powerful. Developed database management systems (DBMS), design automation systems (CAD) for various purposes appear, ACS, APCS, etc. are being improved. Much attention is paid to the creation of application software packages (PPP) for various purposes. New programming languages ​​and systems are still emerging and the existing ones are being developed, the number of which has already reached about 3000. The third-generation computers are most widely used as a technical basis for the creation of large and super-large information systems. An important role in solving this problem was played by the creation of software (DBMS), which ensures the creation and maintenance of databases and data banks for various purposes. A variety of computing and software tools, as well as peripheral equipment has put on the agenda the issues of the effective choice of complexes of software and computing tools for certain applications.

Special mention should be made of the development of third-generation AT in the USSR. To develop a unified technical policy in the field of computing, in 1969, on the initiative of the Union, an Intergovernmental Commission was created with a Coordination Center, and then a Council of Chief Designers. It was decided to create an analogue of the IBM / 360 series as the basis for computing technology in the CMEA countries. For this, the efforts of large research and development teams were concentrated, more than 20 thousand scientists and highly qualified specialists were involved, a large scientific research center for computing technology (NITSEVT) was created, which made it possible in the early 70s to establish serial production of the first models ES EVM. It should be noted right away that the ES computers (especially the first ones) were far from the best copies of the corresponding originals of the IBM / 360 series.

The end of the 60s in the USSR is characterized by a wide variety of incompatible computer technology, which is seriously inferior in terms of basic indicators to the best foreign models, which required the development of a more reasonable technical policy in this strategically important issue. Taking into account a very serious lag in this matter from the computer-developed countries (and, first of all, from the eternal competitor - the USA), the above decision was made, which looked very tempting - to use the tried and tested over 5 years and already well-proven IBM-series with the aim of quickly and cheaply introducing it into the national economy, opening up wide access to very rich software created by that time abroad. But all this was only a tactical gain, and a powerful knockout blow was inflicted on the strategy for the development of domestic computer technology.

The fourth generation of computers

Another revolutionary event in electronics took place in 1971, when an American companyIntelannounced the creation of a microprocessor.Microprocessoris an ultra-large-scale integrated circuit capable of performing the functions of the main unit of a computer - a processor. Initially, microprocessors began to be built into various technical devices: machine tools, cars, airplanes. By connecting a microprocessor with input-output devices, external memory, we got a new type of computer: a microcomputer. Microcomputers belong to machinesfourth generation... A significant difference between microcomputers and their predecessors is their small dimensions (the size of a household TV set) and relatively low cost. This is the first type of computer to hit retail. The most popular type of computers today arepersonal computers (PC).The first PC was born in 1976 in the United States. Since 1980, an American company has become the "trendsetter" in the PC marketIBM... Its designers managed to create an architecture that has become the de facto international standard for professional PCs. Machines of this series were namedIBMPC ( PersonalComputer). The emergence and spread of the PC in its significance for social development is comparable to the emergence of printing. It was PCs that made computer literacy a mass phenomenon. With the development of this type of machine, the concept of "information technology" appeared, without which it already becomes impossible to do in most areas of human activity.Another line in the development of the fourth generation computer is -supercomputer... Machines of this class have a speed of hundreds of millions and billions of operations per second. A supercomputer is a multiprocessor computing complex.

The element base of a computer is large integrated circuits (LSI). The brightest representatives of the fourth generation of computers are personal computers (PCs). Communication with the user was carried out through a color graphic display using high-level languages.

The fourth generation is the current generation of computer technology, developed after 1970.

For the first time, large integrated circuits (LSI) began to be used, which in terms of power approximately corresponded to 1000 ICs. This has led to a decrease in the cost of manufacturing computers.

V1980 it was possible to place the central processor of a small computer on a crystal with an area of ​​1/4 inch (0.635 cm 2 .). LSIs have already been used in computers such as Illiak, Elbrus, and Macintosh. The speed of such machines is thousands of millions of operations per second. The RAM capacity has increased to 500 million bits. In such machines, several instructions are executed simultaneously on several sets of operands.

From the point of view of the structure, machines of this generation are multiprocessor and multicomputer complexes operating on a common memory and a common field of external devices. The capacity of the RAM is about 1 - 64 MB.

The spread of personal computers by the end of the 70s led to a slight decrease in demand for mainframes and mini-computers. This has become a matter of serious concern to IBM (International Business Machines Corporation), a leading mainframe company, and in1979 IBM decided to try its hand at the personal computer market, creating the first personal computersIBMPC.

The machines were intended for a sharp increase in labor productivity in science, production, management, health care, service and everyday life. A high degree of integration contributed to an increase in the density of the layout of electronic equipment, an increase in its reliability, which led to an increase in the speed of the computer and a decrease in its cost. All this has a significant impact on the logical structure (architecture) of the computer and its software. The connection between the structure of a machine and its software becomes closer, especially the operating system (OS) (or monitor) - a set of programs that organize the continuous operation of a machine without human intervention.

Comparative characteristics of computer generations

Specifications

Computer generations

III

Years of application

1948 - 1958

1959 - 1967

1968 - 1973

1974 - present time.

Element base

Electronic tubes - diodes and triodes.

Semiconductor devices.

Small integrated circuits (MIS) containing hundreds or thousands of transistors on one plate.

Large integrated circuits (LSI).

Dimensions (edit)

The computers were housed in several large metal cabinets that occupied entire halls.

The computer is made in the form of racks of the same type... Also, computers were housed in several large metal cabinets, but inIIgeneration decreased in size and weight.

The computer is made in the form of racks of the same type.

A high degree of integration contributed to an increase in the density of the layout of electronic equipment, an increase in its reliability, which led to an increase in the speed of the computer and a decrease in its cost. Compact computers -personal computers.

Number of computers in the world

Dozens.

Thousands.

Tens of thousands.

Millions.

Performance

10 - 20 thousand operations per second.

100 - 1000 thousand operations per second.

1 - 10 million operations per second.

10 - 100 million operations per second.

RAM size

1: 2 kbytes.

2 - 32 kbytes.

64 kbytes.

2 - 5 MB.

Typical models

MESM, BESM-2.

BESM-6, Minsk-2.

IBM-360, IBM-370, ES EVM, SM EVM.

IBM-PC, Apple.

Information carrier

Punch card, punched tape.

Magnetic tape.

Disk.

Flexible and laser drives.

Conclusion

Computer development continues. Fifth generation computer are cars of the near future. Their main quality should be a high intellectual level. In them, input from voice, voice communication, machine "vision", machine "touch" will be possible.

Fifth generation machines are artificial intelligence implemented.

Vin accordance with the generally accepted methodology for assessing the development of computing technology, the first generation was considered , and the fourth - using ... At thatWhile the previous generations improved by increasing the number of elements per unit area (miniaturization), computers of the fifth generation were supposed to be the next step, and to achieve super performance, to interact with an unlimited set of microprocessors.

PC - A desktop or laptop computer that uses a microprocessor as the sole central processing unit that performs all logic and arithmetic operations. These computers are classified as computers of the fourth and fifth generations. In addition to laptops, portable microcomputers also include pocket computers - palmtops. The main features of a PC are the bus organization of the system, high standardization of hardware and software, and an orientation towards a wide range of consumers.

With the development of semiconductor technology, the personal computer, having received compact electronic components, increased its ability to calculate and memorize. And the improvement of the software made it easier to work with computers for people with a very poor understanding of computer technology. Major components: memory card and optional random access memory (PAM); main panel with microprocessor (central processing unit) and place for PAM; PCB interface; drive board interface; a floppy drive device (with a cord) that allows you to read and write data on magnetic disks; removable magnetic or floppy disks for storing information outside the computer; panel for entering text and data.

Now intensive development of the 5th generation computer is underway. The development of subsequent generations of computers is carried out on the basis of large integrated circuits with an increased degree of integration, the use of optoelectronic principles (lasers, holography). Completely different tasks are posed than in the development of all previous computers. If the computer developers from the 1st to the 4th generations were faced with such tasks as increasing productivity in the field of numerical calculations, achieving a large memory capacity, then the main task of computer developers of the 5th generation is to create artificial intelligence of the machine (the ability to draw logical conclusions from the presented facts), development " intellectualization of "computers - removal of the barrier between man and computer. Computers will be able to perceive information from handwritten or printed text, from forms, from a human voice, recognize the user by voice, and translate from one language into another. This will allow all users to communicate with the computer, even those who do not have special knowledge in this area. The computer will be an assistant to man in all areas. .