1. Session - 1 Basics Of Computers VIVEK KUMAR SINGH vivek@bhu.ac.in

2. 8/18/2015Introduction to Computers2 A Desktop Machine

3. 8/18/2015Introduction to Computers3 A Computer System Hardware Software User Hardware Software User

4. 8/18/2015Introduction to Computers4 A Computer System (Contd.) In general, a computer is a machine which accepts data, processes it and returns new information as output. Data Information Processing

5. 8/18/2015Introduction to Computers5 Software Software is set of programs (which are step by step instructions) telling the computer how to process data. Software needs to be installed on a computer, usually from a CD. Softwares can be divided into two groups: - System SW - Application SW

6. 8/18/2015Introduction to Computers6 Software (Contd.) System Software It controls the overall operation of the system. It is stored in the computer's memory and instructs the computer to load, store, and execute an application. Examples: Operating System (OS), Translators DOS, Windows, Unix etc.

7. 8/18/2015Introduction to Computers7 Software (Contd..) Application Software They are Softwares written to perform specific tasks. The basic types of application software are: word processing, database, spreadsheet, desktop publishing, and communication. Examples: MSOffice, Tally, MSOutlook, ISBS, MODBANKER BANKSOFT

8. 8/18/2015Introduction to Computers8 Advantages of Using Computers Speed: Computers can carry out instructions in less than a millionth of a second. Accuracy : Computers can do the calculations without errors and very accurately. Diligence : Computers are capable of performing any task given to them repetitively. Storage Capacity : Computers can store large volume of data and information on magnetic media.

9. 8/18/2015Introduction to Computers9 History of Evolution Of Computers Two Eras: Mechanical Era (Before 1945) Electronic Era (1945 - ) Can be divided into generations. First Generation (1945 – 1954) Second Generation (1955 – 1964) Third Generation (1965 – 1974) Fourth Generation (1975 - )

10. 8/18/2015Introduction to Computers10 Types of Computers On the basis of Computing Power & Size: Laptop / Palmtop Micro Computer / Desktop Mini Computer / Mainframe Super Computer

11. 8/18/2015Introduction to Computers11 Language of Computers Computers only understand the electronic signals. Either Current is flowing or not. Current Flowing : ON Current Not Flowing : OFF Binary Language ON : 1 OFF : 0 Bit, Byte, KB, MB, GB

12. 8/18/2015Introduction to Computers12 Computer Network A Computer Network is interconnection of Computers to share resources. Resources can be : Information, Load, Devices etc.

13. 8/18/2015Introduction to Computers13 Types Of Computer Networks On the basis of Size: Local Area Network (LAN) Its a network of the computers locally i.e. in one room, one building. Wide Area Network (WAN) Its a network of the computers spread widely geographically.

14. 8/18/2015Introduction to Computers14 Benefits of Computer Networks Information Sharing Device Sharing Load Sharing Mobility Fast Communication Anywhere Anytime Banking

15. 8/18/2015Introduction to Computers15 Internet Internet is a huge network of computer networks. Internet provides many services: –E–Email –W–World Wide Web (www) –R–Remote Login (Telnet) –F–File Transfer (FTP)

16. 8/18/2015Introduction to Computers16 End Of Session #1 ANY Queries ??????

17. 8/18/2015Introduction to Computers17 CPU ( Central Processing Unit) The central processing unit (CPU), also known as just a "processor”, is the "brain" of your computer. It contains various electronic circuits.

18. 8/18/2015Introduction to Computers18 VDU (Monitor) This is the television-like screen where the results of a computer's tasks are displayed. Monitors come in all sizes, but most commonly they are either 15 or 17 inches (measured diagonally from one corner of the screen to the opposite corner).

19. 8/18/2015Introduction to Computers19 Keyboard The keyboard looks like a typewriter. It contains all the letters of the alphabet, numbers and some special symbols. It operates like a typewriter keypad, but instead of moving an arm, which strikes the paper, it sends an electronic impulse to the computer, which displays a character on the monitor.

20. 8/18/2015Introduction to Computers20 Its a device that is used to control the computer. A cable connects the mouse to the computer. When the mouse is moved on a pad, called a mouse pad, the cursor on the screen moves. A cursor is a small symbol displayed on the computer screen (normally a diagonal arrow that is used as a pointer) that shows you what the mouse is referencing on the screen. Mouse

21. 8/18/2015Introduction to Computers21 Printer A printer is designed to output information from a computer onto a piece of paper. There are three kinds of printers: dot matrix, laser, and inkjet.

22. 8/18/2015Introduction to Computers22 Scanner A scanner is a device used to copy an image off paper and convert it into a digital image, which can be saved as a computer file and stored on a hard drive. Scanners can also use a special kind of technology called Optical Character Recognition (OCR) to read text from paper and save it as an editable document file

23. Session # 2 Inside The CPU Cabinet

24. 8/18/2015Introduction to Computers24 A Look Inside. Floppy CD

25. 8/18/2015Introduction to Computers25 power supply hard drive motherboard A Look Inside.. CD-ROM drive floppy drive cards

26. 8/18/2015Introduction to Computers26 A Look Inside… Identify all the major components: –P–Power Supply –M–Motherboard –M–Memory –C–Card Slots –C–Cards (sound, video, network) –C–CPU, heatsink and fan –D–Drives (floppy, hard and CD-ROM)

27. 8/18/2015Introduction to Computers27 A Look Inside…. RAM BANK CPU, Fan, HeatsinkCard Slots (ISA & PCI)

28. 8/18/2015Introduction to Computers28 What these components do. Power Supply – (heart) supplies power to all the circuitry and devices. Motherboard – (body) acts as a manager for everything on the computer – connects all the other components together. CPU – Central Processing Unit – (brain) this does all the work of computing.

29. 8/18/2015Introduction to Computers29 What these components do.. RAM – Random Access Memory – (short-term memory) holds data and program instructions that the computer is currently using. Hard Drive – (long-term memory) holds all of the information that needs to be stored between uses of the computer. Floppy and CD-ROM drives – (mouth/ears) allow you to give data to the computer and take data away from the computer.

30. 8/18/2015Introduction to Computers30 What these components do… Card Slots – (fingers) Allows other components to be added to the computer. Video card – (face) Does all of the processing necessary to get stuff looking nice on screen, quickly. Sound card – (vocal cords) Allows sounds from HD or CD-ROM to be played. Network Card – (telephone) allows computer to talk to other computers over a wire.

31. 8/18/2015Introduction to Computers31 Power Supply SMPS – Switch Mode Power Supply Switching Transistors Outputs + 5V, -5V, +12 V, -12 V Typical Costs are: ATX – Rs.700 Non ATX – Rs.300 Usually, SMPS comes with the CPU Cabinet.

32. 8/18/2015Introduction to Computers32 Motherbo ard

33. 8/18/2015Introduction to Computers33 CPU Examples: Intel Family – Pentium 4, 3, 2, Pentium, XEON, Itanium AMD -- Athlon, K62 IBM -- Cyrix Motorola -- 68000 Series CU ALU Memory Registers A Single Chip

34. 8/18/2015Introduction to Computers34 RAM

35. 8/18/2015Introduction to Computers35 Hard Drive We won’t remove this.

36. 8/18/2015Introduction to Computers36 Floppy Drive

37. 8/18/2015Introduction to Computers37 CD-ROM Drive

38. 8/18/2015Introduction to Computers38 Ribbon Cables polarized

39. 8/18/2015Introduction to Computers39 Video Card

40. 8/18/2015Introduction to Computers40 Sound Card

41. 8/18/2015Introduction to Computers41 Back of Computer Remove these screws

42. 8/18/2015Introduction to Computers42

43. 8/18/2015Introduction to Computers43 End of Session # 2 Queries???

44. 8/18/2015Introduction to Computers44 CPU The central processing unit or (CPU) is the "brain" of your computer. It contains the electronic circuits that cause the computer to follow instructions from memory. The CPU contains three main parts, all housed in a single package (Chip): –Control Unit (CU) –Arithmetic Logic Unit (ALU) –Memory BACK

45. Session # 3 Computer Peripherals

46. 8/18/2015Introduction to Computers46 Major Peripherals Keyboard Mouse Hard Disk Floppy Disk CD ROM Printer Scanner Joystick

47. 8/18/2015Introduction to Computers47 Keyboard Keypad contains: –A–Alphabets –N–Numbers –S–Special Symbols –F–Function Keys qwert Keyboard (Typewriter Keyboard). On key press it sends a code (ASCII Code) to the CPU. Plug N Play device. Typical Cost is Rs.300 – Rs.1200

48. 8/18/2015Introduction to Computers48 Mouse Pointing & Click Device. Two / Three Buttons Wheel / Optical Mouse Normally Left Click – Select/ Run Right Click – Popup Menu Typical Cost is Rs.100 – Rs1000

49. 8/18/2015Introduction to Computers49 Hard Disk Magnetic Memory Device. Non-removable storage device. Several Circular Magnetic Disks are housed in a single case. Data is stored as 1s & 0s. Typical Capacity is 20 GB -80 GB Typical Cost is Rs.2200 – Rs6000 Cost/Bit is Low.

50. 8/18/2015Introduction to Computers50 Floppy Disk Magnetic Memory Device. Removable storage. A single circular mylar plastic disk, coated with magnetic material is packed in a protective plastic casing. Typical size is 3.5” & Capacity is 1.44MB Typical Costs are: Floppy Drive -- Rs.300 Floppy Disk -- Rs.10

51. 8/18/2015Introduction to Computers51 CD ROM Optical Device. Removable Storage. Read Only Memory. Typical Capacity is 550 Mb – 800MB Typical Costs are: Drive -- Rs.1000 Disk Rs10 – Rs.35 Related Terms: CD Writer WORM CD RW

52. 8/18/2015Introduction to Computers52 Printer Output Device, Produces Hard Copy Types: –D–Dot Matrix –I–Inkjet –L–Laser Typical Cost Ranges from Rs.3500 – Rs.2 lacs Related Terms: –I–Impact – Non Impact –R–Ribbon, Cartridge, Toner, Duty Cycle Major Vendors in India: –H–HP, Cannon, Samsung, TVS, Epson etc.

53. 8/18/2015Introduction to Computers53 Scanner Input Device, Converts a hard copy into a computer file. Used to Scan Signatures, Photographs etc. Optical Device. Typical Cost Rs.4000 – Rs.75000 Major Vendors in India: –H–HP, Umax, Cannon Nowadays Scanners with OCR produces editable documents.

54. 8/18/2015Introduction to Computers54 End of Session #3 Queries???

55. Session - 4 Overview of Operating System

56. 8/18/2015Introduction to Computers56 What is Operating System OS is system software, which may be viewed as collection of software consisting of procedures for operating the computer. It provides an environment for execution of programs (application software). It’s an interface between user & computer.

57. 8/18/2015Introduction to Computers57 Computer Machine (Hardware) User / Programmer Operating System Human Understandable Language (High Level Language) Machine Language (Low Level Language)

58. 8/18/2015Introduction to Computers58 Types of OS Multiprogramming OS Multitasking/Multiprocessing Multiuser OS Time Sharing OS Real Time OS Distributed OS

59. 8/18/2015Introduction to Computers59 A Second Classification This Classification is based on the type of interface Operating System provides for the user to work in. Character User Interface (CUI) The User has to type the commands on the command prompt to get the work completed. Ex. DOS, UNIX. Graphical User Interface (GUI) The User need not type any commands. He/She just point and clicks on the desired Icon to get the work done. Ex. Windows (9X, XP, NT, 2000), Linux.

60. 8/18/2015Introduction to Computers60 Functions of OS File Management Memory Management Process Management Device Management

61. 8/18/2015Introduction to Computers61 Types of Processing Serial Processing The job is processed at the time when it is submitted. Batch Processing The similar jobs are bunched together and are kept for processing at an later time.

62. 8/18/2015Introduction to Computers62 MS-DOS Overview MS-DOS is an acronym for MicroSoft Disk Operating System It is a CUI based operating system. It provides user with a command prompt (generally called as C:\) where various command could be typed. When one operates in the DOS environment, one interacts with the command interpreter, which interprets the commands given by user. It provides an environment for execution of various application programs like MS-Word, MODBANKER, ISBS etc.

63. 8/18/2015Introduction to Computers63 What is Command It is a string of characters which tells the computer what to do. When one types commands to a computer, one is conversing with the operating system's command interpreter. For example, to copy a file called file.txt from the 3-1/2" floppy drive to the hard drive, one could type C:\> copy a:\file.txt c:\ The word "copy" is a DOS command which causes files to be copied from one location to another

64. 8/18/2015Introduction to Computers64 Entering the DOS Environment If the OS is DOS then the system will directly show prompt (C:\>) If the OS is windows one must either terminate the Windows environment, or open a DOS shell within the Windows environment. I st Method: Terminating Windows Environment Select “Restart in MS-DOS Mode” from Shut Down in Start Menu. II nd Method: Opening DOS Shell in Windows Select Start>Programs>Accessories>Command Prompt (XP) Start>Programs>Accessories>MS-DOS Prompt (98)

65. 8/18/2015Introduction to Computers65 Files and Directory Files A file is a collection of Records. It is the smallest unit of File System (Storage) in a computer. Any document created using computer is a file. This document could either be a letter, any excel sheet, any image or even a database. Directory A collection of files is directory (in DOS) or folder (in Windows) It is analogous to the Office Folder which contains various documents. A directory/folder eases the management of related files/ documents, like the various circulars related to personnel could be placed in a directory called “personnel” and all the circulars related to loans could be placed in a directory called “loans”.

66. 8/18/2015Introduction to Computers66 Filenames in DOS? The filename in DOS have the following format.. It has two parts the name and the extension. The name could be of 8 characters and the extension of 3 characters. The filename can contain alphabets and numbers. It cannot contain any special character other than underscore (_) and also no spaces.

67. 8/18/2015Introduction to Computers67 Organization of files in DOS The DOS file system is a hierarchical file system. Files are collected into directories, and directories may contain both files and other directories. There is always a directory which is not contained by any other, called the root which is represented by the backslash '\' character.

68. 8/18/2015Introduction to Computers68 Organization of files in DOS (Contd.) Concept of Path: Every file can be specified by enumerating all of the directories between the root and it, separated by the backslash '\' character, and appending the file name to the end. The drive which contains the root is specified at the head of the path, separated from the root by a colon (':') The hard drive is most commonly known as the C: drive, and the floppy drives are usually called A:(3-1/2 inch) and B: (5- 1/4 inch).

69. 8/18/2015Introduction to Computers69 Organization of files in DOS (Contd.) / circularsloanspersonnel january february retire.txt rest.txt abc.txt officer.txtnew.dat Fig. Hierarchical Structure of Files

70. 8/18/2015Introduction to Computers70 Some DOS Commands dir: Listing of all the directories. C:\> dir cls: Clears the screen. C:\> cls copy con: Creates a file. C:\> copy con Press Ctrl-Z (^Z) to finish writing. Ex:C:\> copy con test.dat Lets Make UCO a top class Bank. Ctrl-Z (^Z) 1 file(s) copied. (A Message will be shown on the system) This will create a file named test.dat having some data.

71. 8/18/2015Introduction to Computers71 Some DOS Commands (Contd.) edit: Edits a file. C:\> edit This will open a editor window where the contents of file can be seen. These contents could also be edited here and on saving, the contents of file will change. type: Displays the content of a file. C:\> type This will display the contents of file on the computer. The contents of file could only be viewed but could not be changed, as in the case of edit.

72. 8/18/2015Introduction to Computers72 Some DOS Commands (Contd.) md: Make Directory. C:\> md (directory name> This will create a directory with the specified name. cd: Change Directory. C:\> cd (directory name> This will change the directory from current directory to the specified directory. rd: Remove Directory. C:\> rd (directory name> If the directory is needed to be removed permanently from the computer, use this command. For this command to be executed it is necessary that the directory should be empty and user should be on a directory above it.

73. 8/18/2015Introduction to Computers73 Some DOS Commands (Contd.) copy: Copies a file. C:\> copy This will copy the file from the source location to the specified destination. The command creates a copy of the file on the destination i.e. the file would be found on both the location. move: Moves a file. C:\> move This will move the file from the source location to the specified destination. The file from the source location would be removed and would be moved to the destination.

74. 8/18/2015Introduction to Computers74 Some DOS Commands (Contd.) ren: Renames a file. C:\> ren This will change the name (rename) of the file to a new name as specified. del: Deletes a file. C:\> del This will delete the file permanently from the system.

75. 8/18/2015Introduction to Computers75 Overview of Windows Windows is an GUI based operating system. It is also developed by Microsoft Corporation, which is headed by Mr. Bill Gates. Over the years the Microsoft have evolved various versions of Windows. Win95, Win98, Win2000, Win ME, Win NT, Win XP. It gives user a handy environment where he doesn’t have to remember and learn the syntaxes of various commands as is the case in DOS. The user can just point and click on the Icons provided to him on the screen.

76. 8/18/2015Introduction to Computers76 Folders and Documents Folders are a way to organize your documents within drives in Windows as are the directories in DOS. A document is each thing that you create on a computer. A document can be made using any type of software.

77. 8/18/2015Introduction to Computers77 End of Session #4 Queries???

78. 8/18/2015Introduction to Computers78 QUIZ 1.Name any four devices of a Computer. Keyboard, Mouse, Scanner, Light Pen. 2.What is the job of CPU? Central Processing Unit controls and coordinates all the activities of the computer.

79. 8/18/2015Introduction to Computers79 QUIZ 3.What is the unit of measuring the speed of the processor? Mega Hertz or Kilo Hertz ( No. of CPU Cycles/second) 4. What is a computer network? It is interconnection of computers to make a LAN,MAN or WAN.

80. 8/18/2015Introduction to Computers80 QUIZ 5.Name any three storage devices. Hard Disk, Magnetic Tape, Compact Disk. 6.What is command to create directory? C:\>MD >

81. 8/18/2015Introduction to Computers81 QUIZ 7.What is Internet? It is the network of networks. 8.What are different types of printers? Dot Matrix Printer, Inkjet Laser

82. 8/18/2015Introduction to Computers82 QUIZ 9. What is the use of Scanner? It is used to copy the real image on paper to be stored as digital image in the computer. 10. Why Operating system is required? It is required to provide the interface between the user and the computer.

83. 8/18/2015Introduction to Computers83 QUIZ 11.What is the difference between Primary Storage and Secondary Storage? Primary Storage is temporary storage, fast and costly. Secondary storage is permanent, slow and cheap.

84. 8/18/2015Introduction to Computers84 QUIZ 12. What is MODEM. Why it is required? It is Modulator Demodulator. It is used to connect the PC to the Internet using Analog Telephone Lines. 13.What is the maximum length of file name in DOS? First Name- 8 characters, Last Name- 3 characters.

85. 8/18/2015Introduction to Computers85 QUIZ 14. What is the command in DOS to see the contents of the file? C:\> Type > 15. What are the two types of Software? Systems Software Application Software