1. Rupali Dhir Faculty Computer Department , PCTE
Introduction to IT
Rupali Dhir
Faculty
Computer Department , PCTE

2. Introduction A computer is a programmable electronic machine.
Computer is derived from word “COMPUTE” which means to calculate, and that can perform arithmetic operations at a very high speed.
Computer operates upon data and gives out useful information.

3. Computer
A computer is an electronic machine that can accept data (input), process it into useful information (output), and store it in a storage device for future use.
PROCESS
OUTPUT
INPUT
Input
Process
Output

4. Computer

5. Introduction
Hardware refers to the physical equipment used for the input, processing, output and storage activities of a computer system.
Central processing unit (CPU) manipulates the data and controls the tasks performed by the other components.
Primary storage internal to the CPU; temporarily stores data and program instructions during processing.
Software refers to the part that we can not touch. Programs that run such as Word, Messenger etc.

6. Introduction
Secondary storage external to the CPU; stores data and programs for future use.
Input technologies accept data and instructions and convert them to a form that the computer can understand.
Output technologies present data and information in a form people can understand.

7. Introduction

8. Introduction
Computer Stores or process information in 1 and 0. Which are called bits.
Combination of 8 bits are called Byte and so on as follows …
8 bits = 1 Byte
1024 Bytes = 1 Kilo Byte (KB)
1024 Kilo Bytes = 1 Mega Byte (MB)
1024 Mega Bytes = 1 Giga Byte (GB)
1024 Giga Bytes = 1 Tera Byte (TB)

9. Block Diagram

10. Components of computer
Input devices
Output devices
CPU
ALU
Control Unit
Secondary Storage / Memory

11. Characteristics Of Computer
Automatic : Machines that work by itself without any human intervention. Eg. Robots
Speed : It is measured in terms of microseconds, nanoseconds (10-9) and picoseconds.
Accuracy : Computers produce accurate results.
No I.Q.: A computer does only what it is programmed to do. It cannot take its own decision in this regard
No Feelings: Computers are devoid of emotions. Their judgment is based on the instructions given to them in the form of programs that are written by us (human beings)

12. Characteristics Of Computer
Diligence : Computer is free from tiredness & lack of concentration.
Versatility : Computer is capable of performing variety of tasks depending upon instructions given.
Power of Remembering.
No Intellectual Power : It does not have its own intelligence.

13. Classifications of computer on the basis of Function
Analog
E.g. Mechanical Watch
Digital
Digital Watch
Hybrid
ECG machines in hospital

14. Classifications of computer on the basis of size
Supercomputers
Mainframe Computers
Mini Computers
Desktop Pc’s
Notebooks

15. Super Computer Super Computer : The biggest in size.
It can process trillions of instructions in seconds.
This computer is not used as a PC in a home neither by a student in a college.
Used by Govt for different calculations and heavy jobs.
Used for animation purposes in most Hollywood Movie’s

16. Super Computer

17. Mainframes It can also process millions of instruction per second.
It can handle processing of many users at a time.
It is commonly used in Hospitals, Air Reservation Companies as it can retrieve data on huge basis.
This is normally to expensive and out of reach from a salary-based person.
It can cost up to thousands of Dollars.

18. Mainframes

19. Mini Computers
These computers are preferred mostly by small type of business personals, colleges etc.
These computers are cheaper than above two.
Its an intermediary between microcomputer and mainframe.

20. Micro / Personal Computers
It is mostly preferred by Home Users.
Cost is less compared to above.
Small in size.
A microcomputer contains a microprocessor (a central processing unit on a microchip ), memory in the form of read-only memory and random access memory , I/O ports and a bus housed in a unit that is usually called a motherboard .

21. Micro / Personal Computers

22. Personal Computers
Notebook computers typically weigh less than 6 pounds and are small enough to fit easily in a briefcase.
Principal difference between a notebook computer and a personal computer is the display screen.
Many notebook display screens are limited to small resolution.

23. PDA or Handheld Computers
Handheld computer is a pocket-sized computing device, typically having a display screen with touch input or a miniature keyboard.
Some manufacturers are trying to solve the small keyboard problem by replacing the keyboard with an electronic pen.
A pocket computer is a small calculator-sized handheld programmable computer.
It has only RAM maximum upto 1GB and Hard disk capacity is 80GB.

24. History Abacus Mechanical Calculator Difference Engine
Analytical Engine
1944 MARK I
Howard Aiken at
Harvard University
UNIVAC1
first commercial computer
Hewlett and Packard
Met and setup shop in
Garage at Silicon valley

25. History
Abacus

26. History
Difference Engine
Analytical Engine

27. History
UNIVAC 1

28. Bill Gates with Paul Allen
History
1969 – Internet was founded
1975 – Microsoft Founded
Bill Gates with Paul Allen
1976
Apple
                    
     
1981-IBM PC
PC was introduced.
1989 – WWW
Invented by
Tim Berners-Lee

29. Jim Clark and Marc Andreesen
History
1994 – Netscape
Founded by
Jim Clark and Marc Andreesen
Many more….

30. Generations of Computers

31. Generations Of Computer
1st Generation
2nd Generation
3rd Generation
4th Generation
5th Generation

32. 1ST GENERATION (1944 - 1958) : VACUUM TUBES
Used thousand of vacuum tubes
They were fastest calculating devices.
Too large in size
Large amount of heat due to thousands of vacuum tubes, so air conditioning was required
High power consumption
Frequent hardware failure due to burn out of tubes
Costly to manufacture and maintain these computers
The first computer using vacuum tubes was ENIAC

33. 1ST GENERATION (1944 - 1958) : VACUUM TUBES IBM Punched Card (input)
Magnetic Tapes (output)
Vacuum Tubes
(memory)

34. UNIVAC
ENIAC

35. 2ND GENERATION (1959 - 1964) : TRANSISTOR
Use of transistors instead of vacuum tubes
These transistors were made of solid material, some of which is silicon, therefore they were very cheap to produce
Easier to use and handle
No burning out, but hardware failures were still there
Almost ten times faster than tubes
Much smaller than vacuum tubes and generate less heat.
Less expensive to produce but still costlier

36. 2ND GENERATION (1959 - 1964) : TRANSISTOR
Produce less heat as compared to tubes but air conditioning was required
High level programming languages such as FORTRAN, COBOL were used
Easier to program these computers
Batch operating system was used

37. 2ND GENERATION ( ) :
TRANSISTOR

38. 3RD GENERATION (1964 - 1970) : INTEGRATED CIRCUIT
In 1958, Jack St. Clair Cilby & Robert Noyce invented integrated circuits
IC’s consist of several electric components like transistors, resistors and capacitors embedded on a single chip of silicon
More powerful & faster than second generation computers.
Smaller in size and require small space for installation
Require less power and produce less heat but still need proper air conditioning
Faster and large memory

39. 3RD GENERATION ( ) :
INTEGRATED CIRCUIT

40. 4TH GENERATION (1971- PRESENT) :
INTEGRATED CIRCUIT
Use of IC’s with VLSI technology Very Large-scale integrated (VLSI).
Microprocessors and semiconductor memory
Larger memory because of larger hard disks and floppy disks and magnetic tapes as portable storage media
Very less heat hence no air conditioning was required instead fans were used

41. 4TH GENERATION (1971-PRESENT):
INTEGRATED CIRCUIT
Graphical User Interface operating systems were used
Very easy to manufacture & maintain them and cost very less
Very fast as compared to computers in early generations
Microprocessors led to the invention of personal computers.

42. 4TH GENERATION (1971-PRESENT) :
MICROPROCESSOR

43. 5th GENERATION -PRESENT & BEYOND
IC’s based on ULSI technology
Portable PC’s (notebook computers) were much smaller and handy
Much faster and powerful than computers in earlier generations
Consume very less power
Less costlier and easy to maintain
Newer and more powerful applications make computers more easy to use in every field

44. 5th GENERATION -PRESENT & BEYOND
Consume very less power
Less costlier and easy to manufacture and maintain
Newer and more powerful applications make computers more easy to use in every field
Artificial Intelligence (AI) concerns with making computers behave and think like humans.
AI studies include robotics, expert systems, games, etc..

45. 5th Generation (Present & Beyond) : Artificial Intelligence
AI studies include robotics, expert systems, games, etc.

46. Input Devices
Key Board
Mouse
Light Pen
Tablet or Digitizer
Joystick

47. Input / Output Devices
Provide means of communication between a computer
and outer world
Also known as peripheral devices because they
surround the CPU and memory of a computer system
Input devices are used to enter data from the outside
world into primary storage
Output devices supply results of processing from
primary storage to users

48. Keyboard A keyboard's primary function is to act as an input device.
The standard keyboard has101 keys
Most Common is the QWERTY keyboard
Typing keys
A numeric keypad
Function keys
Control keys

49. WORKING OF KEYBOARD
KEYBOARD IS A INPUT DEVICE USED FOR ENTERING DATA INTO COMPUTER BY PRESSING ONE KEY AT
ONE TIME.
KEYBOARD CONTROLLER
KEYBOARD BUFFER
SYSTEM SOFTWARE
CPU

50. MOUSE
A MOUSE IS A HANDMOVABLE INPUT DEVICE THAT CONTROL THE POSITION OF CURSOR ON THE SCREEN

51. WORKING OF MOUSE

52. Optical mouse

53. TRACK BALL
TRACK BALL IS A POINTING DEVICE THAT USE A BALL TO POISTION THE CURSOR AND WORK LIKE A UPSIDE DOWN MOUSE

54. Light Pen

55. JOYSTICK
CLICK BUTTON
STICK
SOCKET
LIGHT INDICATOR
BALL

56. Digitizer
A DIGITIZER IS A INPUT DEVICE USED FOR CONVERTING PICTURES,MAPS AND DRAWING INTO DIGITAL FORM FOR STORAGE IN COMPUTER.