This ppt discuss with the basic concept of computer, characteristics, components of computer, generation of computer, computer languages and so on

1. Dr. K. VETRIVEL,
Assistant Professor,
Department of Economics,
Bharathidasan University,
Tiruchirappalli – 620 023

2. Concept of Computer
 A computer is a programmable machine designed to perform arithmetic and
logical operations automatically and sequentially on the input given by the user
and gives the desired output after processing. Computer components are
divided into two major categories namely hardware and software. Hardware is
the machine itself and its connected devices such as monitor, keyboard, mouse
etc. Software are the set of programs that make use of hardware for performing
various functions.
 An electronic machine can store and process information. It is defined as
stored program digital computing system.
 A Computer is an electronic device of wires, transistors, circuits, instructions
and data can transmit, store and manipulate information.
 A Computer is a machine that accepts data and processes that data (data may
be numbers, letters or both or even sounds). Information is turned into
electrical pulses so that it may be processed by sorting, collating and deleting
mathematical manipulation and other forms of data processing.

3. Characteristics of Computer
 SPEED : In general, no human being can compete to solving the complex computation,
faster than computer.
 ACCURACY : Since Computer is programmed, so what ever input we give it gives result
with accuratly.
 STORAGE : Computer can store mass storage of data with appropriate formate.
 DILIGENCE : Computer can work for hours without any break and creating error
 VERSATILITY : We can use computer to perform completely different type of work at the
same time.
 POWER OF REMEMBERING : It can remember data for us.
 NO IQ : Computer does not work without instruction.
 NO FEELING : Computer does not have emotions, knowledge, experience, feeling.

4. Computer and its components
 Computer : Computer itself a combination of different type of
separate electronic device. i.e. Computer only will be computer if
it has INPUT DEVICE, PROCESS UNIT, and OUTPUT DEVICE.
 Central Processing Unit (CPU) : It is heart and mind of the
computer without this unit computer unable to process.
 Keyboard : This is an input device which is used to input the data
into the computer.
 Mouse : This is also an input device which is used to input the
data into the computer.
 Monitor : This is an output device which is used to show the
result of the instructions.
There are variety of monitor available in the market such as,
CRT Monitor, LCD Monitor, Touch Screen Monitor, TFT Monitor
etc.

5.  Switched Mode Power Supply (SMPS) : This is and
electronic device which is used to manage the power supply
of computer.
 Hard Disk (HDD) : This is used to store the data in massive
amount. There are so many type of HDD available in the
market, i.e. SATA, PATA, External HDD, Internal HDD.
 Printer : This is an out put device which is used to show the
result on the paper. There are plenty of printer available in
the market like inkjet, Laser printer, dot matrix printer etc.
 Universal Serial Bus (USB) : This is used to connect the
external device to the computer

6.  Ethernet Cable : This is used to connect computer with other computer.
 CD/DVD ROM : This is used to store the data.
 Speaker : This is an output device which is used to listen voice, songs, etc.
 Mike : This is an Input device which is used to record the sound .
 Laptop : This is complete computer which can be carried anywhere any time.
 Netbook : This is called mini laptop which is generally lighter and smaller than
laptop.
 Random Access Memory (RAM) : This is called primary memory. This is also
called main memory of the computer. Whatever data is written in this memory,
is lost after switching off the system.

7.  Read Only Memory (ROM) : This is called primary memory. Data is written in
this memory by the vendor of the computer permanently.
 Pen Drive : This is very popular device now a days for carrying data on move.
 Blue Ray Disk : This is same as CD/DVD but only different is it can store multi
time of data from CD/DVD and faster than CD/DVD.
 Scanner : This is an input device which is used to scan the document for the
soft copy.

8.  LCD : It is known as Liqued Crystal Display. It is an output
device as monitor.
 Motherboard : It is a combination of electronic circuits.
 Sound Card : This is also a combination of electronic circuits
which helps to give out put in the form of sound.
 Graphics Card : This is also a combination of electronic circuits
which helps to give output the data into the monitor.

9. Functions of computer
 Input - Computer receiver information from users. A user enters
information using input devices like keyboard, mouse or any
other devices like webcam, punch card, magnetic tapes, joystick
or magnetic disk etc. The Input unit accept information using
input devices then it convert the given data to readable form and
this data moves to Central Processing Unit (CPU).
 Storage - The given information stored in a computer using
different storage devices i.e. central process unit and auxiliary
memory. The auxiliary memory also known as secondary or
external storage have hard devices for example Floppy, Hard
Disk, Compact Disk and Flash Drive. These different storage
devices have both advantages and disadvantages. Auxiliary
storage speed up information and store it long term and
permanently.
Functions of computer

10.  Processing - It is considered the basic computing
operation. It execute the instructions, control storage
data and input or output devices attached the
computer.
 Output - Last but not the least the output unit which
represents results from the operations of central
processing unit CPU. The result may be in hard or soft
form i.e. visual display unit, printers and headphones.

12. Computer Software
Software is a logical programme to handle/solve the complex problem.
 System Software : This is special type of software which is responsible
for handle the whole computer system.
 Application Software : This is special type of software which is used to
solve a particular problem.
 Embeded Software : This type of software embeded with hardware to
do a specific type of job.
 Proprietary Software : In general, this type of software require to
purchase to use that particular software for the sometime or single user
as per conditioned by the vendor of that particular software.
Open Source Software : This type of software may be freely
available and can not be use in commercially. We can modify, and use it
under the same license.

13. Computer Languages
 Machine Level Language : This is low level programming
language. Computer or any electronic device only understand
this language. i.e. Binary number i.e 0 and 1.
 Assembly Level Language : This is a low level programming
language which is converted into executable machine code by a
utility programmer referred to as an assembler.
 High Level Language : High level language is a programming
language which is easily understandable/readable by human.
 Interpreter : This is a convertor which converts high level
language programme to low level language programme line by
line.
 Compiler : This is also a convertor which converts whole high
level language programme to low level language programme at a
time.

14. Number System
 Binary Number System : It has only base 2 i.e 0 and 1
 Octal Number System : Base of octal is 8 i.e. 0, 1, 2, 3,
4, 5, 6, 7
 Decimal Number System : Base of Decimal is 10 i.e. 0 1
2 3 4 5 6 7 8 9
 Hexadecimal Number System : Base of this number
system is 16 i.e. 0 1 2 3 4 5 6 7 8 9 A B C D E F

15. Operating System
 Windows : This is an Proprietary Operating system
and vendor is Microsoft. i.e. Windows 2007, Windows
vista, Windows 2008 etc.
 Linux : This is an open source Operating System such
as ubuntu, fedora, debian, mandriva, centOS etc.
 Linux (Ubuntu ) Desktop Elements
 File Management in Linux (Ubuntu)

16. Computer Security
 Virus and worms : These are the computer programme
which malfunction the computer system. Virus requires a
carrier while worms does this by itself. Worm does not
requires any carrier.
 Spoofing : Through this, deceiving the computer users and
making the fool.
 Intrusion or Hacking : If a computer is used and controlled
by unauthorised users then it is called hacking and who
does this is called hacker. Main purpose of hacking to steal
the private data or alter the actual data.
Denial of Services: The main aim of this attack is to
bring down the targeted network and make it to deny the
service for legitimate users.

17. Generation of the Computer
Charlse Babbase is known as father of computer
he has invented first analytical computer in year 1822
 First Generation (1940 – 1955) . Example : Electronic
Numerical Integrator and Computer (ENIAC) , EDVAC
 Second Generation (1956 – 1965) : IBM 1401
 Third Generation (1966 – 1975) : IBM System/360
 Fourth Generation (1976 – 1985) : Macintosh 128k
 Fifth Generation (1986 -till date) : Super computer

18. Classification of Computer
Computers differ based on their data processing
abilities. They are classified according to purpose, data
handling and functionality.

19. According to functionality
 Analog Computer - An analog computer (spelt analogue in
British English) is a form of computer that uses continuous
physical phenomena such as electrical, mechanical, or hydraulic
quantities to model the problem being solved.
 Digital Computer - A computer that performs calculations and
logical operations with quantities represented as digits, usually
in the binary number system
 Hybrid Computer (Analog + Digital) - A combination of
computers those are capable of inputting and outputting in both
digital and analog signals. A hybrid computer system setup offers
a cost effective method of performing complex simulations.

20. On the basis of Size
 Super Computer - The fastest and most powerful type of computer
Supercomputers are very expensive and are employed for specialized
applications that require immense amounts of mathematical
calculations. For example, weather forecasting requires a
supercomputer. Other uses of supercomputers include animated
graphics, fluid dynamic calculations, nuclear energy research, and
petroleum exploration.
 The chief difference between a supercomputer and a mainframe is that
a supercomputer channels all its power into executing a few programs
as fast as possible, whereas a mainframe uses its power to execute many
programs concurrently.

21.  Mainframe Computer - A very large and expensive computer capable of
supporting hundreds, or even thousands, of users simultaneously. In
the hierarchy that starts with a simple microprocessor (in watches, for
example) at the bottom and moves to supercomputers at the top,
mainframes are just below supercomputers. In some ways, mainframes
are more powerful than supercomputers because they support more
simultaneous programs. But supercomputers can execute a single
program faster than a mainframe.
 Mini Computer - A midsized computer. In size and power,
minicomputers lie between workstations and mainframes. In the past
decade, the distinction between large minicomputers and small
mainframes has blurred, however, as has the distinction between small
minicomputers and workstations. But in general, a minicomputer is a
multiprocessing system capable of supporting from 4 to about 200
users simultaneously.

22. Micro Computer or Personal
Computer
 Desktop Computer: a personal or micro-mini computer
sufficient to fit on a desk.
 Laptop Computer: a portable computer complete with an
integrated screen and keyboard. It is generally smaller in
size than a desktop computer and larger than a notebook
computer.
 Palmtop Computer/Digital Diary /Notebook /PDAs: a
hand-sized computer. Palmtops have no keyboard but the
screen serves both as an input and output device.

23. Workstations
A terminal or desktop computer in a network. In
this context, workstation is just a generic term for a
user's machine (client machine) in contrast to a
"server" or "mainframe."

24. Thank you