1. arosha_g@yahoo.com 071-8221172

2. Data- row facts Information - convert to more useful & meaningful form Data processing is just like making a cake

3. arosha_g@yahoo.com 071-8221172 DataInformationProcess Data (row facts) Numbers, words, image, sound Eg: List of my friends Information (Processed data or data has been convert to more useful & meaningful form Eg: list can arrange in ascending order (A to Z )

4. arosha_g@yahoo.com 071-8221172 InputOutputProcess Input Devisers Output Devisers

5. arosha_g@yahoo.com 071-8221172 Please correct the pg 4 Data / Instructions Command /Signal Flow Block diagram Of computer System

6. arosha_g@yahoo.com 071-8221172

8. Input Devises Keyboard, Mouse Light pen Digital Camera Scanner Joy stick Fingerprint scanner Touch screen Magnetic strip reader Graphic tablets Microphone Optical character recognition (OCR) Video recognition

9. arosha_g@yahoo.com 071-8221172 Keyboard Convert letters, numbers and other characters into electronic signals 1.Typing keys 2.Numeric keypad 3.Function keys 4.Control keys

10. QWERTY is the most common modern-day keyboard layout The name comes from the first six keys appearing on the top left letter row of the keyboard and read from left to right: Q-W-E-R-T-Y. The QWERTY design is based on a layout created for the typewriter arosha_g@yahoo.com 071-8221172

11. Mouse Pointing device 1.Ball underneath rolls 2.Laser to sense the motion

12. arosha_g@yahoo.com 071-8221172 PS 2 Mouse USB Mouse

13. arosha_g@yahoo.com 071-8221172 Light pen Pointing device Light sensitive pen like devise ( help to draw )

14. arosha_g@yahoo.com 071-8221172 Digital Camera No film roll Capturing videos Photos can directly move into the computer without scanning

15. arosha_g@yahoo.com 071-8221172 Scanner Convert text, drawing, photos in to digital form that can Stored and edit in computer

16. arosha_g@yahoo.com 071-8221172 Joy stick Joy stick (Pointing device) Pointing devise Help to play video games

17. arosha_g@yahoo.com 071-8221172 Fingerprint scanner Pointing device Use to scene finger prints for security reasons, or time attendance

18. arosha_g@yahoo.com 071-8221172 Touch screen (Pointing device) Display screen that receives input from the touch of a finger( ATM screens in banks) (Input and output both)

19. arosha_g@yahoo.com 071-8221172 Magnetic strip reader Used as credit card, railway tickets, time attendance, debit cards

20. trackball arosha_g@yahoo.com 071-8221172

21. Magnetic Ink Character Recognition, (MICR) MICR codes can be easily read Cheque numbers

22. arosha_g@yahoo.com 071-8221172 Optical character recognition,(OCR) Optical character recognition, conversion of images of text into characters

23. arosha_g@yahoo.com 071-8221172 OMR- Optical mark recognition Optical mark recognition is the process of capturing human-marked data from document forms such as surveys and tests.( Eg: MCQ

24. barcode reader (or barcode scanner) arosha_g@yahoo.com 071-8221172

25. Graphic tablets (Pointing device) Like electronic tracing paper Use for CAD

26. arosha_g@yahoo.com 071-8221172 Microphone Input sound

27. arosha_g@yahoo.com 071-8221172 O UTPUT D EVICES

28. arosha_g@yahoo.com 071-8221172 MONITOR (Visual Display Unit ) The computer monitor, screen or VDU (Visual Display Unit) is the most common output device. Advantages - relatively cheap and reliable, can display text and graphics in a wide range of colours. They are also quiet and do not waste paper. Disadvantages - no permanent copy to keep and unsuitable for users with visual problems.

29. arosha_g@yahoo.com 071-8221172 MONITOR Cathode ray tubes (CRTs) Liquid crystal displays (LCDs)

30. arosha_g@yahoo.com 071-8221172 CRT Less Sharpness than LCD Takes large space than LCD Flicker No limited viewing angle cheaper than LCD large energy consumption when compare with LCD CRT monitor's response time is negligible

31. arosha_g@yahoo.com 071-8221172 LCD Sharp pictures Takes very little space( Slim) Flicker-free screens are easy on the eyes limited viewing angle Fairly expensive Use less energy and generate less heat than CRTs Slower response time (response time is the time it takes for the pixel to update the colours you see on screen.)

32. arosha_g@yahoo.com 071-8221172 Speakers and head phones Taking sound out of the computer Some computer displays have rather basic speakers built-in. Laptops come with integrated speakers

33. impact vs non impact printer arosha_g@yahoo.com 071-8221172

34. daisywheel http://www.youtube.com/watch?v=CT BM9JELUYQhttp://www.youtube.com/watch?v=CT BM9JELUYQ Daisy wheel printing is an impact printing technology invented in 1969 arosha_g@yahoo.com 071-8221172

35. Dot-Matrix printer Less expensive Noisy Producing the image by striking paper through the ribbon Low quality print out Very slow

36. arosha_g@yahoo.com 071-8221172 Ink Jet-printer Cheaper than laser Not that noisy Technology-ink flowing through the appropriate nozzles. Quality than dot matrix Faster than dot matrix

37. arosha_g@yahoo.com 071-8221172 Laser-printer Expensive Very silent in operation Work with toners Very High quality print outs Very fast

38. plotter arosha_g@yahoo.com 071-8221172

39. projector, a device that projects an image on a surface. arosha_g@yahoo.com 071-8221172

40. SECONDARY STORAGE Hard Disk Floppy Disk Optical Disk Storage Magnetic tape

41. arosha_g@yahoo.com 071-8221172 Hard Disk non-volatile storage device which stores digitally encoded data on rapidly rotating platters with magnetic surfaces

42. arosha_g@yahoo.com 071-8221172 Hard Disk

43. arosha_g@yahoo.com 071-8221172 Floppy Disk

44. arosha_g@yahoo.com 071-8221172 Floppy Disk 1.44 Mb Disk hidden in a plastic jacket 5¼-inch (133 mm), and the newest and most common 3½-inch (90 mm) Portable an outdated medium

45. arosha_g@yahoo.com 071-8221172 Zip Disks Zip disk 100-750Mb better than floppy portable and removable An outdated medium

46. arosha_g@yahoo.com 071-8221172 Optical Disk Storage CD- 650-700MB DVD-2GB-8GB optically written on its surfers CDROM-compact disk read only memory WORM-write once read only memory Rewritable CD. DVD - Digital video disk /(digital versatile disc) same dimensions as a CD but stores up to 6 times as much information

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49. DVD Digital Versatile Disk (DVD)

50. arosha_g@yahoo.com 071-8221172 Magnetic tape Similar to audiotapes store data in serial manner Accessing speed is Low Can store very large capacity of data (used for back ups )

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52. Main memory

53. arosha_g@yahoo.com 071-8221172 RAM Random access memory Storing programs witch is currently running and data witch is being processed Volatile memory where the information is lost after the power is switched off

54. arosha_g@yahoo.com 071-8221172 ROM Read only memory Contents permanently etched into the memory chip at the manufacturing stage ROM stands for Read Only Memory, and is a memory chip which only allows data to be read from it, and will not allow data to be written onto it Non Volatile memory

55. arosha_g@yahoo.com 071-8221172 Cache memory Very fast memory, that is use to improve the speed of the PC It act as an intermediate store between the CPU and main memory

56. arosha_g@yahoo.com 071-8221172 Computer Ports

57. arosha_g@yahoo.com 071-8221172 PS/2 connector A mini DIN plug containing 6 pins. Developed by IBM for connecting the keyboard (purple ) and mouse (green ) Shape -Round

58. arosha_g@yahoo.com 071-8221172 Parallel port connector for scanners and printers The 25-pin port

59. arosha_g@yahoo.com 071-8221172 Serial Port A 9-pin D-type connector meeting EIA-232 standard. Possibly used to connect some trackballs, mice, modems and monitors.

60. arosha_g@yahoo.com 071-8221172 VGA port the 15-pin plugs and sockets that connect the computer to the monitor. used to connect a monitor

61. arosha_g@yahoo.com 071-8221172 USB- Universal Serial Bus A single USB port can be used to connect up to 127 peripheral devices, FAST Plug and Play Hot plugging /hot swapping

62. Hot plugging /hot swapping. The ability to add and remove devices to a computer while the computer is running and have the operating system automatically recognize the change. Two external bus standards -- Universal Serial Bus (USB ) and IEEE 1394 -- support hot plugging. This is also a feature of PCMCIA. Hot plugging is also called hot swapping. arosha_g@yahoo.com 071-8221172

63. Ethernet (or Network) Port used to connect with internet /network

64. arosha_g@yahoo.com 071-8221172 Hardware The term hardware describes the physical parts of your computer which you can physically touch or see such as your monitor, case, disk drives, microprocessor and other physical parts.

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66. Software

67. arosha_g@yahoo.com 071-8221172 software collection of computer programs, procedures and documentation that perform some tasks on a computer system.

68. arosha_g@yahoo.com 071-8221172 Hardware System Software Application Software USER

69. arosha_g@yahoo.com 071-8221172 Application Software examples of software applications are word processors, spreadsheets, and media players, database applications.

70. arosha_g@yahoo.com 071-8221172 System software System software such as operating systems, which interface with hardware to provide the necessary services for application software,