FUNDAMENTAL OF ICT
TOPIC :

INTERNAL AND EXTERNAL PARTS OF COMPUTER

APPLICATION SOFTWARE
INTERNAL COMPONENTS OF COMPUTER

Internal is a term used to describe a device that is installed in the
computer.Internal components are used for processing and storing

Eg video card,motherboard,RAM etc. are internal devices and
printer, scanner are external devices.
Parts of computer
Internal components of computer

Mother Board

Processor

RAM (Random access memory)

ROM (Read only memory)

Video Card

Expansion Slots

Sound Card

Power Supply
Internal devices
Mother board

The mother board is the main circuit board where all other computer components are placed or are
connected, it is consider as a backbone of the PC. INTEL,ASUS,Aopen are manufacturer of the
motherboard.

The motherboard type will determine what kind of processor, and memory chips can be installed
on the computer along with what kind of external connections USB are supported. It includes
many component such as central processing unit(CPU),Random access memory, sound and video
card, expansion slots etc.
Processor

The microprocessor is most important part of computer as it process
information and control every part of computer system.

It is a integrated electronic circuit that perform calculations that run a
computer, it can perform arithmetic/logical, I/O and other basic instruction
that are passed from an operating system and it is placed inside a small socket
& middle of the mother board and top of executing code of our programs, it
also control how other computer components communicate & operate .

Processor speed is measured in megahertz and now recently gigahertz with
higher number representing more processing power. It perform basic function
like fetch,decode,execute and write back and they are classified as per word
length such as 8-bit,16 bit,32 and 64 bit microprocessor

Types of microprocessor:

Single-core CPU- One core inside a single CPU that handle all the processing

Dual –core CPU- Two cores inside a single CPU in which both cores can process
information at the same time.

Triple-core CPU- Three cores inside a single CPU that is actually a quad processor with
one of the cores disable.

Quad core CPU- four core inside a CPU

Hexa core CPU- six core inside a CCPU

Octa core CPU- eight core inside a single CPU
Random Access Memory(RAM)

RAM is a primary temporary storage unit used to store data and program in
computer that is located on the mother board.

RAM is a volatile memory, all information that is stored in RAM is lost when
computer is turned off.

The RAM chip may be mounted on the motherboard or in sets of several chips
on a small board connected to the motherboard. Older memory types were in
form of chips called dual-in line package.

Advantages

Ram uses much less power than disk drives and it is fastest storage device.

Disadvantages

Ram cost per bit is high and it has limited memory space.
Types of RAM

Static RAM

It is a memory chip that is used as a cache memory.SRAM is much faster than DRAM
and does not have to be refreshed as often. SRAM is much more expensive than
DRAM.

Dynamic RAM-

It is a memory chip that is used as main memory.DRAM must be constantly refreshed
with pulses of electricity to maintain the data stored within chip.
Read Only Memory(ROM)

ROM a memory from where we can only read but cannot write on it.ROM is nonvolatile memory. ROM stores such instruction which can require to start a
computer.The operation referred to as bootstrap.
Types of ROM

MROM(Mask ROM)-the very first ROM was hard wired device that contain preprogramed set of data & instruction .

These were inexpensive MROM.

PROM(Programmable read only memory)- it is a read only memory that can be
modified once by user and cannot be erased.The user buy blank PROM and enters the
desired content using a PROM programmer .

EPROM( Erasable and programmable read only memory)-

It is a type of memory chip that retains its data when its power supply is switched off.

The EPROM can be erased by exposing it to Ultra-violet light for a duration upto 40
min.
EEPROM(Electrically Erasable and Programmable Read only Memory)
EEPROM is a type of non-volatile memory,it is programmed and erased electrically and
it can be erased and programmed about 10 thousand times.Both erasing and
programming takes about (4 to 10 ms).

It can erase one byte at a time rather than erasing a entire chip.it is less cost than RAM
but it takes more power and increase in size as number of input variable increases.
Video card

The video card is an expansion card that allows the computer to send graphical
information to video display device such as monitor, tv or projector.

Some other names for video card are graphics card,graphics adapter, display adapter,
video controller etc. manufacturer of video cards are mainly ASUS, Nvidia, AMD.
Sound card

Sound card allows computer to output ,record and manipulate sound. Personal computer
have built in sound card.

The sound card is an expansion card that allows the computer to send audio information
to an audio device like speakers, headphones etc.

Sound card are configure and utilized with the help of software application and a device
driver. The input device to receive audio data is usually a microphone and the device
used to output audio data is speaker or headphone.

Most of the music collection is probably in digital format, either on CD or files of
computer. In order to be able to listen music a sound card coverts digital data to analog
sound waves we can hear. The output signals is connected to a speaker or headphones

We can use a sound card to record audio with a microphone and audio software can
alter the sound.
Expansion slot

A expansion slot is a socket on the motherboard that is used to insert an expansion card
or circuit board which provides additional features to computer such as video
card,sound card,graphics, ethernet or memory.

Depending on the form factor of the case and motherboard a computer system generally
can have anywhere from 1 to 7 expansion slots. These slots are placed back panel of the
computer and allow us to install devices to upgrade the system.

Some slots like an AGP (Accelerated graphics port)slot are used exclusively for video
cards,but most of the slots on modern systems are generic PCI(peripheral component
interconnect)-X slot that are used for all cards. ISA(Industry standard architecture )is a
type of bus used in PC’s for adding expansion card.for eg ISA may be used to add a
video card ,network card or an extra serial port.Todays most computer only support PCI
and AGP expansion card.
Power Supply

The power supply is located in one corner of the back side of the computer case.

On the side that faces out of the computer it has a single plug for our power cable and
opening for the cooling fan.

A power supply is an hardware device that supplies electrical power to all computers
internal devices, it receives power from electrical outlets and convert current from
AC(Alternating current) to DC (direct current).

It also regulates voltage to an adequate amount, which allows the computer to run
smoothly without overheating.

Power supply is rated or calculated in terms of watt, the more powerful the computer,
the more watts it can provide to components.
External Devices of computer
External Devices

The external devices or components (peripherals) of hardware are the parts that we can touch ,for eg
monitor,mouse,keyboard ,printer. These components are used either to get data into or out of the
computer system and these components are referred as input or output devices( I/O)
Input Devices:

An input device feeds data to the computer system for processing. Eg webcam, keyboard,digital camera etc.
Output Devices:

Output devices provide or display the result of data to the user after processing the input data.Eg
graphics,audio,video,monitor etc.
Input Devices & Output devices
Input Devices

Keyboard

Mouse

Voice Input system ( eg microphone)

Video input devices (Digital camera, webcam, barcode reader, scanner)

Optical character reader

Light pen

Composite devices (joystick,gamepad,biometric,touch screen,digitizers)
Output devices

Monitor( LCD,LED)

Printer ( dot matrix,inkjet,laser printer)

Plotter(flat bed,inkjet ,pen,thermal plotter)

Projector

Scanner (flat-bed, sheet-fed,hand held scanner)
Input devices
keyboard

Keyboard is a input device used today and the instructions, data are input by typing on the
keyboard. The message typed on the keyboard reaches the memory unit of a computer.

It
is
connected
to a computer using cable
and it has 104 keys in keyboard
including(alphabet,number,functional,special ,navigation keys present on keyboard.
Mouse

Mouse is a pointing device which controls the movement of cursor. It perform different function
like click, double click, dragging, scrolling, moving up and down. The sensor in the mouse notifies
speed of its movement to the computer.
Video input system
Microphone

This device converts spoken words ito machine language form. A microphone is used to convert human
speech into electric signals.

The signal pattern is then transmitted to a computer when its compared to dictionary of patterns that have
been previously placed in a storage unit of computer. When a close match is found, the word is
recognized.

Audio input devices are used to capture sound, audio input devices allow a user to send audio signals to a
computer for processing,recording,carry out commands.

Microphone is an input device to input sound that is then stored in a digital form and it is used in various
application such as adding sound to a multimedia presentation, or for mixing music.
Video input devices
Digital camera

It converts graphics directly into digital form. Digital camera first capture the images those images are
transferred to the computer when the camera is connected to the computer. When light falls on the chip
through the lens, it converts light waves into electric waves. . Mostly digital camera are in jpeg format .
Webcam

A webcam is a digital camera connected to computer. It can send live pictures from wherever its sited to
another location by means of internet.

Many desktop comes with a built in camera and microphone but we can add a separate webcam at any
time.webcam does not have any built in storage it is connected to computer and uses the computer hard
drive as its storage.
Barcode reader

Barcode reader is a device reads barcodes and convert them into electric pulses to be processed by
computer.

Barcode is data coded in form of light and it is machine readable code in the form of a pattern
vertical line of varying widths.
Scanner

scanners are used to enter information directly it into the computers memory it works like xerox
machine.

The scanner converts any type of printed or written information including photographs into digital
pulses,which can be manipulated by the computer.
Types of scanner
Flat-bed scanner

A flat bed scanner is type of optical scanner used to scan printed text and images and save into
computer storage as a digital file. It works on principle of photocopier machine. Firstly cover of
scanner is picked up then printed page is placed on glass-surface of scanner then scanner is
instructed through computer software to scan the pages with help of light and save digital file into
computer storage. It is widely used in offices,schools,universities or general use
Sheet-feed scanner

They are smaller than flat bed scanner we feed a document or photo in bunches into the scanner
automatic document feeder ,rather than place it on the top of the surface one photo or document at
a time. Most sheet feed scanner these days are quite fast and loaded with features for capturing and
processing data.
Hand-held scanner

It is a lightweight, small and portable scanner and it is used to scan small amount of data such as
short articles from newspaper.

It is moved over the text pages or image slowly from start to end.it scans quality may be lower
than other scanners but it is used to capture small amount of data or images quickly.
Flat-bed scanner
Sheet-feed scanner
Hand-held scanner
Optical character reader

It is device which detect alpha-numeric characters printed or written on computer.OCR is the
process that converts an image of text into a machine –readable text format.

Benefits of OCR are storage capacity, data security, makes document editable, cost reduction.
Light pen

This is an input device which is used to draw lines or figures on a computer screen.

Instruction or data can be written with the help of light pen instead of using
keyboard.
Composite devices
Composite devices- it is a input devices which combine two different forms of input and
these devices consist of functions like movement or scrolling, provide buttons for clicking
and controlling the task.
Joystick

Joystick is pointing device which is used to move cursor position on monitor screen.
The joystick is having a spherical balls at its lower and upper ends.The joystick can
moved in all four directions.

Function of joystick is similar to mouse and it controls speed of cursor rather than its
absolute position. It is used for computer games,controlling industrial robots.
Biometric (thumb,finger reader)

Biometrics are automated methods of recognizing a person based on physiological
characteristics.Among the features measured are face, fingerprints, iris, voice,
handwriting.

Biometric data is separate and distinct from personal information.NO one can misuse
biometric information as it differ from person to person.

Biometrics readily available in education sector, banking, public or government sectors
for identification of person.
Output device
Monitor

Monitor is a output device which is a piece of hardware that displays the video,text,graphics
information generated by the computer.

A monitor is referred to as a screen,display,video display, video screen and it is same as television
but usually display information at a much higher resolution.
Types of monitor

LCD (Light crystal display)

LED (light emitting diode)

PDP (Plasma display panel)
PRINTER

A printer is an external output device that accept text and graphic output from a computer and
transfer the information to computer. usually to standard size of sheets of paper called as hard
copy.

Printer are different in size, speed, complex and cost.

More expensive printers are used for higher-resolution, colour printing.
Types of printer

Dot matrix printer

Ink jet printer

Laser printer
Plotter

Plotter is an output device that is used to produce graphical output on paper.it uses single colour or
multi colour pens to draw pictures .

It is a graphic printer that uses ink pens to draw the images.The pens are move on surface of
paper.plotters can only draw data in vectors graphics format,graphics that are made of straight
lines,,curved lines ,different shapes.
Types of plotter

Drum plotter

Flatbed plotter

Electrostatic plotter
Projector

A projector is a output device used to take an image from a video source like video
adapter and project it on a screen.

Projectors comes in different shapes, sizes which are manufactured by different
companies.

Projector are used in variety of different ways they are used as home theatre due to their
ability to project movies and television programs onto the screen, in conferences
,meeting projectors are used to display the information or idea of project to the
audience.
EXTERNAL STORAGE DEVICES
TYPES OF STORAGE DEVICES
Primary storage device

RAM
Secondary storage device

Magnetic Tape

Magnetic disk (Hard disk, floppy disk)

Optical disk (CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-R, DVD-RW)

Pendrive
External storage device is divided into two types:

Primary storage- it stores the data temproraily and when the computer is switched off
the data get erased from the primary storage eg RAM and it is called as volatile
memory.

Secondary storage –It is a permanent storage or used for backup data it has large
storage space for storing data and programs than primary storage. Storage device is
mainly divided into two types as follows:

Magnetic devices ( hard disk, magnetic tape, floppy disk)

Optical devices (CD , DVD, Pen drives)
Magnetic tape

It is a oldest storage device. It is made up of plastic coated with magnetic material, large data is
stored on magnetic tape in the form of magnetic spots.

It is used to read and write data on tape. magnetic tape is a sequential access device, it is slower
disk than magnetic disk or optical disk. magnetic tapes are used in reels of different lengths for eg
200,600,1200 feet etc. data stored on magnetic tape can be read again and again just as in sound
tape recorder.

Organization of magnetic tape

The device that stores computer data on magnetic tape is called tape drive. Magnetic tape is
divided into vertical columns called frames and horizontal rows called as channels or tracks. In
magnetic tape data is stored in a string of frames with one character per frame and each frame
spans multiple tracks ( usually 7 to 9) tracks.single bit is stored in each track ,that is one byte per
frame. The last track stores the parity bit which is used to detect or control errors in tape. When
the byte is written to magnetic tape the nos of 1’s is counted ,the parity bits is used to make nos of
1’s even or odd. The nos of characters that can be recorded in one inch of tape is called tape
density typically tape density are 800 bits per inch 1600bpi and 6250 bpi.
Working of magnetic tape

Magnetic tape drive uses two reels ie supply reels and take up reels. Both reels are
placed on hub of magnetic tape and the tape moves from supply reels to take up reels.

When the tape passes under read / write head ,the data can be read or write or
transferred to the primary memory & read from primary memory and written onto the
tape.
Magnetic disk

A magnetic disk is thin circular metal or plastic disk coated with magnetic material.data is
stored in the form of magnetic spot.it is a random access device and it is faster than magnetic
tape. There are 3 main types of magnetic disk ie hard disk, floppy disk, zip disk.
Hard disk

The hard-disk is called as fixed disk . It consist of one more metal plates plates are fixed in
the drive and metal plates are coated with magnetic material to store data. A motor rotates
disk ,there is also access arm and read /write head to read and write data on disk.

Advantage – larger storage capacity and stores retrieve data much faster than a floppy disk
usually fixed inside the computer.

Disadvantage- if the head crashes it can damage the surface of the disk,leading to loss of
data in that sector.

It is fixed inside the computer and cannot easily be transferred to another computer.
Floppy disk

It is a small plastic plate coated with magnetic material.data is stored in magnetic spots .floppy
disk(FDD) is used to read and write data on floppy disk.

Data stored in floppy disk in concentric circles called as track and tracks are divided into many storage
location called as sectors.

FDD performs basic functions like rotating the disk or reading/writing onto the disk.the disk rotate at 360
rpm while reading or writing on it.

The FDD drive circuit board receives instructions for reading or writing the data on to the disk through
the floppy disk controller.

In FDD motor is located below the disk causing disk to spin.

Advantages – it is portable and inexpensive and data on floppy disk can be accessed randomly

Disadvantage –storage capacity is limited only 1.44 mb and access time is slow about 84ms
Optical disk

An optical disk is an computer disk that uses optical storage techniques to store or read write
data.laser technology is used to read or write data on disk.

Laser stands for light amplification through emission of radiation .laser beam writes on the surface
of optical disk by creating very small holes. presence of hole represent 1 and absence of hole
represent 0.

Types of optical disk are as follows

CD-ROM(compact disk read only memory)- the data stored in this drive is can only be read
cannot be delete or changed. It is portable storage device and it can easily transfered from one
computer to another computer.

It can commonly store data upto 750 mb and it can also store large amount of data like
software,audio-video data .

CD-R(CD recordable or write once read many)- it is a blank disk and user can store
data on it once.we can write data once and can read many times.the device to store data
on CD-R is called CD writers or CD-burners.

CD-RW(compact disk rewritable)- It is a special type of disk where user can write
data on it,if there is error in writing data,he may erase the content and rewrite the data
again.CD-writers are used to store data on CD-RW.
DVD-ROM

DVD is digital video disk is similar to a CD but has larger storage capacity and enormous
clarity.Depending upon the disk type it can store several gigabytes of data.

DVD’s are used to store music or movies and can be played back on our television or the computer too. It
can store up to 17 Gb or more data.

DVD-ROM is pre-recorded and it can contain data like movies, videos, software etc user cannot change
data or delete data from DVD-ROM.it is read only.
Types of DVD

DVD-R(DVD-Recordable)- it is a blank disk, user can store data only once. It is normally used to
store HD (HIGH DEFINITION)video movies. DVD writers are used to store data on DVD-R.

DVD-RW(Digital video disk rewritable)-user can write data on disk many times by erasing the old
data.
Pendrive

Pendrive
is
a
portable
device
which
allows
user
to
transfer
data
(text,images,documents,videos etc).to and from computer easily.

User can easily read and write the data on the pendrive by plugging it into the USB port
on the computer.

Pendrive can run without battery and draw power from the USB connection itself.

Both floppy disk and CD’s are now being gradually replaced by pendrive because data
transfer and storage capability is much faster rate.

Other names include flask drive jump drive, thumb drive.
APPLICATION SOFTWARE

Application software is a term which is used for software created for a specific purpose

Software can perform various task for the user, such as word
processing,accounting,budgeting etc

List of application softwares
a)
Word processing software (Microsoft word, word pad, google docs)
b)
Spreadsheet softwares (Microsoft excel)
c)
Database software (Microsoft access, oracle,sql server)
d)
Presentation software (power point)
e)
Photo editing software (Microsoft paint, adobe photoshop)
f)
Video editing software(adobe premiere pro,we video)
g)
Graphics manipulation software (image edit)
h)
Measuring software
Application software

Word processing software- It is process of manipulation of text using computer.It includes
entering, formatting & manipulation of text on a computer screen and printing of the processed
textThe main purpose of word processing software is to produce document.A word processor is a
software program capable of storing, creating, printing typed document.

a)
Eg Microsoft word(MS Word)It is a word processing software developed by Microsoft.It was launched in 25 oct 1983.
b)
It is mainly designed text for presentation.
c)
MS-word includes different functions such as save the document,correct error,word count, font
size,font style,apply a style, customize a style,page size,page margin,insert header and footer.
Spread sheet software

Spread sheet software was developed by DAN BRICKLIN in 1978 .

First spread sheet termed as “visicalc”(visible calculator)

Spread sheet is an interactive computer application for organization,
analysis and storage of data in tabular form (table format)

It consist of sheets having a rows and columns

The spreadsheet allows user to create, modify, manage large set of data. It also help in applying
mathematical formulae and functions, creating graphics, diagrams and charts.

Spreadsheet software is used to maintain budget, financial statements, grade sheets, sales records and also
used by teachers, marketers, financial analyst.
Database software

Database is a collection of related data.This software organize and managed data.

A computer system which is responsible for storing large amount of data, retrieval of
data from database is called database management system.

It allows user to create, define, maintain,manipulating, control access to the database.

Features of database are filtering, sorting,creating forms etc and DBMS able to bring
information stored in separate tables using query language

Eg Microsoft access,oracle,sql server,mysql.

Oracle relational database software was developed by larry elision and bob miner in 1977
and it is used in offices,educational settings,organization.
Presentation software

Presentation is the process of presenting a topic to an audience.

A presentation is a collection of data which is presented with help of
images,charts,graphics,animation,sound,video.

The presentation include insertion, formatting, editing, texting, themes.

Eg Power point presentation, keynotes

Power point is developed by Robert Gaskin, Dennis Austin in 1987.
Identify the peripheral devices
THANK YOU