Informatics

Informatics and Computer Technologies

Structure of a Personal Computer (hardware) A personal computer consists of hardware

and software Hardware includes all physical

components of the computer Software includes all programs, which

permit the hardware to do its functions and problems which are set.

A system device is the main component of the computer and includes all main modules, which define its functions.

Motherboard

A motherboard is a physical and logical main stand of the personal computer. All components and devices are connected to it. Parameters of the motherboard define the possibilities of the computer for upgrading in future.

CPU (Central Processing Unit)

CPU defines the computing power, does the “thinking” function of the computer

The main characteristic of a CPU is bar frequency in MHz

Bar frequency defines the number of the operations, which are done per unit of time, i.e., as much as the bar frequency is higher, so the computer “thinking” is faster

MemoryMemory

Central Processing Unit needs Central Processing Unit needs memory to do calculating operation. memory to do calculating operation.

The size and architecture of the The size and architecture of the memory are important for the level memory are important for the level of difficulties of the problems, which of difficulties of the problems, which it can solve. it can solve.

There are two kinds of memory: There are two kinds of memory:

ROMROM

ROM ROM – read only memory (without ability for changing), – read only memory (without ability for changing), which saves data and programs, that are necessary for the which saves data and programs, that are necessary for the operations of the computer in a static way. Its content is save operations of the computer in a static way. Its content is save even when the computer is turned off. even when the computer is turned off.

The user doesn’t have access to it. The user doesn’t have access to it. BIOSBIOS- Basic - Basic Input/Output System is recorded on this memory – a number Input/Output System is recorded on this memory – a number of programs, which send data to the system, identifying the of programs, which send data to the system, identifying the machine, do test procedures, programs, that permit user’s machine, do test procedures, programs, that permit user’s software of to take control over the hardware and etc.software of to take control over the hardware and etc.

RAMRAM RAM RAM (Random Access Memory)-memory, in (Random Access Memory)-memory, in

which data which data andand programs programs, that are used at the , that are used at the current moment for execution of tasks are current moment for execution of tasks are loaded dynamically. loaded dynamically. The content of this The content of this memory disappears memory disappears whenwhen the computer is the computer is turned ofturned offf. . The sThe size of thize of thee memory memory reflects on reflects on the fastness of the executed programmes. the fastness of the executed programmes.

RAM RAM is measuris measureded in megabytes in megabytes (MB)(MB) -- 1 MB 1 MB is about 1 million symbols.is about 1 million symbols. In the modern In the modern computers, computers, that use Wthat use Windows, indows, it is it is recommendrecommended to ed to ususe e at least 32 MB memory. at least 32 MB memory. It is good to use 64 MB memory with It is good to use 64 MB memory with multimedia products – graphics, images, multimedia products – graphics, images, sound and animation.sound and animation.

Extending slotsExtending slots

Extending slotsExtending slots are are special slots on the special slots on the motherboard, motherboard, which are used which are used when new when new components are components are added added - sound - sound card, video card, card, video card, and internal and internal modemmodem..

InputInput -- output portsoutput ports InputInput -- output ports are output ports are

special slots for special slots for attaching attaching input-output input-output devicesdevices - mouse, printer, - mouse, printer, and scanner. and scanner.

They are situated on the They are situated on the back panel of back panel of the the system device. system device.

Usually Usually the personal the personal computercomputer has two has two serialserial ((COM1, COM2) COM1, COM2) or one or one parallel (LPT1)parallel (LPT1) port port

SSerial ports provide two-erial ports provide two-ways connection and ways connection and they they are slower.are slower.

A A parallel port is one-parallel port is one-wayway -- only for exit and only for exit and usually usually it is used it is used for for a a printer.printer.

New computers have New computers have a a serial serial (USB)(USB) port, which port, which is faster. It is used for is faster. It is used for installing of installing of printers; printers; special devisesspecial devises - GSM - GSM - - connectionconnection..

KeyboardKeyboard This is the oldest This is the oldest

device for insertion device for insertion of data and handing of data and handing over commands to over commands to the computer. It the computer. It works on a type-works on a type-writer principlewriter principle

In addition to these In addition to these buttons, there some buttons, there some more buttons on the more buttons on the keyboards that are keyboards that are used for the used for the computer only.computer only.

A mouseA mouse

It is invented to make ones work more comfortable and It is invented to make ones work more comfortable and faster. The mouse has two or three buttons. When the faster. The mouse has two or three buttons. When the left button is pressed, one indicates the place for the left button is pressed, one indicates the place for the mouse to stop, marks some option, file or place in the mouse to stop, marks some option, file or place in the text. A menu appears, when the right button is text. A menu appears, when the right button is pressed, which shows the operations that can be done pressed, which shows the operations that can be done at the certain moment. Functions can be set on the at the certain moment. Functions can be set on the third button.third button.

A trackball (static mouse) A trackball (static mouse) and and

a light pen a light pen A trackballA trackball - There is a - There is a

build-in little ball in some build-in little ball in some keyboards. When it spines in keyboards. When it spines in different directions, it different directions, it controls the moving on the controls the moving on the screen and with the help of screen and with the help of two additional buttons the two additional buttons the pressing of the left and the pressing of the left and the right button of the mouse is right button of the mouse is simulated.simulated.

A light penA light pen - It is like a - It is like a usually pen, trailing by a usually pen, trailing by a cable to the system device. cable to the system device. Computer registers the place Computer registers the place where the pen points. It is where the pen points. It is used for special functions - used for special functions - for drawing or work with for drawing or work with graphical images.graphical images.

ScannerScanner

It is used to read images on paper and transform them It is used to read images on paper and transform them into comprehensible for the computer graphic files, into comprehensible for the computer graphic files, which can be seen on the screen, inserted in text which can be seen on the screen, inserted in text documents and various application, printed out and documents and various application, printed out and processed by the use of graphic programs. Some processed by the use of graphic programs. Some models of scanners can scan negatives and slides.models of scanners can scan negatives and slides.

A MonitorA Monitor

A monitor is a compulsory part of the computerA monitor is a compulsory part of the computer It is controlled by a video controller (video card), which is situated It is controlled by a video controller (video card), which is situated

on the motherboard and transforms the data from the computer on the motherboard and transforms the data from the computer into signals that are comprehensible, for the monitorinto signals that are comprehensible, for the monitor

Monitors follow certain standards, and for the new monitors it is Monitors follow certain standards, and for the new monitors it is SVGA SVGA and dividing capacity 1and dividing capacity 1280х1024.280х1024. The dividing capacity The dividing capacity defines the quality and thickness of the imagedefines the quality and thickness of the image

Important feature of the monitor is the frequency of Important feature of the monitor is the frequency of refresh raterefresh rate of of the image, which is measured per second. At a higher frequency the image, which is measured per second. At a higher frequency of the image, the screen is refreshed often and the winking of the of the image, the screen is refreshed often and the winking of the screen is avoided, though invisible it can cause tiredness at work screen is avoided, though invisible it can cause tiredness at work for long time.for long time.

A printer A printer

A printer is used to print out documents A printer is used to print out documents and images. and images.

There are three types of printers There are three types of printers depending on the technology of workdepending on the technology of work MatrixPrinterMatrixPrinter Ink Cord PrinterInk Cord Printer Laser PrinterLaser Printer

Some types of printersSome types of printers

SoundSound

There is a built – in, miniature inner speaker in a personal There is a built – in, miniature inner speaker in a personal computer. Its function is to bring out elementary sounds that computer. Its function is to bring out elementary sounds that accompany some of the operations of the computer – deletion of a accompany some of the operations of the computer – deletion of a programme, starting of Windows and etc.programme, starting of Windows and etc.

It is necessary a sound card, so one can listen to musical It is necessary a sound card, so one can listen to musical compact discs and use some programmes and supplement that compact discs and use some programmes and supplement that carry out sound information.carry out sound information.

It enables the computer to process sounds of any kinds and to It enables the computer to process sounds of any kinds and to control other signal expressing devices. For the reproduction of control other signal expressing devices. For the reproduction of the sound it is necessary speakers to be switched on, but for a the sound it is necessary speakers to be switched on, but for a record, a microphone ought to be attached at the back panel side record, a microphone ought to be attached at the back panel side of the system box.of the system box.

ModemModem

A modem is necessary for establishing a connection of A modem is necessary for establishing a connection of a computer and a telephone line or cable television net. a computer and a telephone line or cable television net.

The modems that are used for connection with these The modems that are used for connection with these two nets are different. two nets are different.

They transform the received data from the computer They transform the received data from the computer into suitable for the telephone or cable net signals. into suitable for the telephone or cable net signals.

Modem is used for a connection with another computer Modem is used for a connection with another computer or Internet.or Internet.

Devices and Carriers for Devices and Carriers for recording datarecording data

For the operating of the computer, it is necessary to For the operating of the computer, it is necessary to have space on the computer, where to save the have space on the computer, where to save the programmes and data. Basically this function is done programmes and data. Basically this function is done by the hard disc. by the hard disc.

There are many devices for archiving or reinstalling There are many devices for archiving or reinstalling data on other computers - floppy disc, magnet optical data on other computers - floppy disc, magnet optical device, CD-ROM and DVD.device, CD-ROM and DVD.

The capacity of the devices and carriers and for The capacity of the devices and carriers and for recording data is measured in MB, and at the new recording data is measured in MB, and at the new computers in GB. 1 GB is equal to 1000 megabyte or computers in GB. 1 GB is equal to 1000 megabyte or 1GB can contain more than thousand million symbols 1GB can contain more than thousand million symbols or nearly 600 000 pages.or nearly 600 000 pages.

Hard DiscHard Disc

Another important feature of the Another important feature of the computer is the volume of the saved computer is the volume of the saved data on the hard disc. data on the hard disc. Scanned documents – issues, Scanned documents – issues, covers of books, photos, and covers of books, photos, and archive documents and etc. need archive documents and etc. need more space to be saved. more space to be saved. Depending on the measures and Depending on the measures and quality of the scanned image, the quality of the scanned image, the parameters vary between parameters vary between 1010 to to 200 200 КВ, КВ, t. e. fore 1500 scanned figures; t. e. fore 1500 scanned figures; it will be necessary it will be necessary 100 МВ 100 МВ disk disk space.space.

Floppy Disc DeviceFloppy Disc Device

A floppy disc device is a part of A floppy disc device is a part of the standard configuration of the standard configuration of the computer. It is used for the computer. It is used for reading and recording data on reading and recording data on the diskette. The current the diskette. The current standard capacity of the standard capacity of the diskette is 1, 44 MB.diskette is 1, 44 MB.

Diskettes can be used for Diskettes can be used for archiving of data and archiving of data and transmitting them to another transmitting them to another computer. computer.

Magnet – optical discMagnet – optical disc

Magnet – optical disc requires magnet – Magnet – optical disc requires magnet – optical device. optical device.

It is used for archiving and transmitting of It is used for archiving and transmitting of data of large volume. data of large volume.

Today, it is not used so often, because it is Today, it is not used so often, because it is slower than the hard disc and CD-ROM slower than the hard disc and CD-ROM devices.devices.

Compact Disc DevicesCompact Disc Devices

There are two typesThere are two types: : CD-ROM –CD-ROM – for reading of compact discfor reading of compact disc only only and and CD-WR – CD-WR – for reading and recording on itfor reading and recording on it.. They have a great They have a great capacitycapacity - 650, 700, 750 МВ. - 650, 700, 750 МВ.CD-ROM –CD-ROM – for reading becomes a standard part of the computer for reading becomes a standard part of the computer device, because they have a number of advantages: they save in a device, because they have a number of advantages: they save in a reliable way a great volume of data. That saves space on the hard reliable way a great volume of data. That saves space on the hard disc. disc. Recording Recording CD-WR CD-WR devicesdevices are also preferable devices for archive are also preferable devices for archive and exchange of a great volume of data. A reliable archive of data and exchange of a great volume of data. A reliable archive of data base can be created with such a devicebase can be created with such a device.. Compact discs work on the optical principle. Mono-recordable Compact discs work on the optical principle. Mono-recordable CD-R CD-R (CD-R - Compact Disk - Recordable) - Compact Disk (CD-R W - (CD-R - Compact Disk - Recordable) - Compact Disk (CD-R W - Compact Disk - Rewriteble – Compact Disk - Rewriteble – and and Recordable(CD-R W - Compact Recordable(CD-R W - Compact Disk – RewritebleDisk – Rewriteble) for multi-records. ) for multi-records.

DVD devicesDVD devices

They also can be of two types – for They also can be of two types – for reading and for recording data. reading and for recording data.

Digital technology is used when data are Digital technology is used when data are recorded, which offers maximum recorded, which offers maximum frequency on recording of image and frequency on recording of image and soundsound

A Personal Computer