computer fundamental slides BBA Vth semester (C.C.S. University Meerut)

1. UNIT II
INPUT & OUTPUT DEVICES
Prepared By:-
MAYUR GOEL

2. INPUT
• INPUT IS THE PROCESS OF ENTERING THE DATA AND TRANSLATING INCOMING
DATA INTO MACHINE READABLE FORM,

3. OUTPUT
• OUTPUT IS THE PROCESS OF PROVIDING RESULTS AND CONVERTING IT FROM
MACHINE READABLE FORM TO HUMAN READABLE FORM.

4. INPUT DEVICES
Typing Pointing Audio visualsScanning
Keyboard
Mouse
Joystick
Touch screen
Light pen
Digitizer
OCR
OMR
OBR
MICR
Voice
recognition
Microphone
Digital camera
Video camera

5. KEYBOARD

6. • USING KEYBOARD, A USER CAN TYPE A DOCUMENT AND PERFORMS OTHER NUMEROUS
TASKS.
• MOST KEYBOARD HAVE BETWEEN 80-110 KEYS INCLUDE FOLLOWING-
• 1. TYPING KEYS- LETTERS OF ALPHABET HAVING STANDARD PATTERN QWERTY.
• 2. NUMERIC KEYS- A SET OF 20 NUMBER KEYS
• 3. FUNCTION KEYS- (F1-F12)12 FUNCTION KEY USED BY APPLICATIONS AND OPERATING
SYSTEM TO INPUT SPECIFIC COMMAND.
• 4. CONTROL KEYS- USED TO CONTROL THE CURSOR ON SCREEN.(ARROW KEYS, HOME,
END, PAGE UP, PAGE DOWN, INSERT, DELETE, CTRL, ALT, ESC, WINDOWS OR START KEY )
• CTRL, ALT, SHIFT ALSO KNOWN AS THE MODIFIER KEYS BECAUSE THEY ARE USED TO
MODIFY THE FUNCTIONING OF A NORMAL KEY.

7. MOUSE

8. • INVENTED BY ENGELBART IN 1963.
• USED ONLY ON GUI .
• USED TO HANDLE THE POINTER EASILY ON THE SCREEN TO PERFORM
VARIOUS FUNCTIONS.
• IT HAS TWO BUTTONS AND A SCROLL WHEEL.
• MOUSE MAY PERFORM THE FOLLOWING OPERATIONS:-
• 1. POINT
• 2. CLICK
• 3. DRAG
• 4. SCROLL

9. • THERE ARE THREE TYPE OF MOUSE-
• 1. MECHANICAL MOUSE- (BALLAND AN ELECTRONIC CIRCUIT
CONTAING SENSORS PLACED AT BOTTOM )
• 2. OPTICAL MOUSE- (BALL PLACED INSIDE THE MOUSE)
• 3. WIRELESS MOUSE- (CORDLESS MOUSE, AND MOVEMENT IS DETECTED
THROUGH RADIO WAVES.)

10. JOYSTICK

11. • A JOYSTICK IS A CURSOR CONTROL DEVICE WIDELY USED IN COMPUTER GAMES.
• IT CONSIST OFA HANDHELD LEVER THAT PIVOTS ON ONE END AND TRANSMITS ITS
COORDINATES TO A COMPUTER.
• LEVER OF JOYSTICK CAN MOVE IN ALL THE DIRECTIONS .
• IT IS SIMILAR TO MOUSE BUT WITH MOUSE, THE CURSOR WILL STOP MOVING AS SOON
AS YOU STOP MOVING THE MOUSE.
• HOW EVER IN CASE OF JOYSTICK, THE POINTER CONTINUES MOVING IN THE
DIRECTION TO WHICH THE JOYSTICK IS POINTING.

12. TOUCH SCREEN

13. • A TOUCHSCREEN IS A DISPLAY SCREEN THAT CAN IDENTIFY THE OCCURRENCE AND
POSITION OF A TOUCH THE SCREEN USING BY FINGER.
• THE TOUCHSCREEN FACILITATES THE USER TO INTERACT WITH WHAT IS DISPLAYED
ON THE SCREEN IN A STRAIGHT FORWARD MANNER RATHER THAN IN AN INDIRECT WAY
BY USING A MOUSE OR A TOUCHPAD.
• TOUCH SCREENS ARE WIDELY USED IN ATM, POS (POINT OF SALE), AND OTHER TYPE OF
APPLICATION THAT REQUIRE THE USER TO INPUT AND RECEIVE INFORMATION
INSTANTLY.

14. LIGHT PEN

15. • IT USES A PHOTOELECTRIC (LIGHT SENSITIVE) CELLAND AN OPTICAL LENS (TIP)
MOUNTED IN A PEN SHAPED CASE.
• WHEN WE MOVE TIP OF PEN OVER THE SCREEN SURFACE, IT DETECTS THE LIGHT
EMITTED FROM A LIMITED FIELD OF VIEW OF THE MONITOR’S DISPLAY.
• THE SYSTEM TRANSMITS THIS ELECTRONIC RESPONSE TO A PROCESSOR, WHICH
IDENTIFIES THE MENU ITEM.
• THE PEN HAS A FINGER OPERATED BUTTON, WHICH THE USER CLICKS TO SELECT
AN OPTION FROM THE SCREEN.

16. DIGITIZER
• DIGITIZER USED FOR CONVERTING (DIGITIZING) PICTURES, MAPS, AND
DRAWING INTO DIGITAL FORM FOR INPUT TO COMPUTER.

17. OPTICAL DEVICES/ SCANNING DEVICES
• OPTICAL DEVICES ALSO KNOWN AS DATA SCANNING DEVICES, USE LIGHT AS A
SOURCE OF INPUT FOR DETECTING OR RECOGNIZING DIFFERENT OBJECTS SUCH
AS CHARACTERS, MARKS CODES AND IMAGES.
• THESE OPTICAL DEVICE CONVERTS THE OBJECTS INTO DIGITAL DATAAND SEND IT
TO THE COMPUTER.

18. OCR
OPTICAL CHARACTER RECOGNITION

19. • OCR IS THE PROCESS OF CONVERTING PRINTED MATERIAL INTO TEXT
OR WORDPROCESSING FILES THAT CAN BE EASILY EDITED AND STORED.
• STEPS;-
• SCANNING THE TEXT CHARACTER BY CHARACTER.
• ANALYSING THE SCANNED IMAGE TO TRANSLATE THE CHARACTER
IMAGE INTO CHARACTER CODES.
• IT DETECT THE LIGHT AND DARK AREAS TO IDENTIFY THE IMAGE
ALPHABET OR NUMERALS.
• IT FACILITATES TO STORE THE TEXT DOCUMENT IN THE FORM OF TEXT
RATHER THAN AN IMAGE WHICH OCCUPY LESS SPACE

20. OMR
OPTICAL MARK RECOGNITION

21. • OMR IS THE PROCESS OF ELECTRONICALLY EXTRACTING THE DATA FROM MARKED
FIELDS, SUCH AS CHECKBOXES AND FILL-IN FIELD, ON PRINTED FORMS.
• THE OMR SHEET IS SCANNED BY THE READER TO DETECT THE PRESENCE OFA MARK
BY MEASURING THE REFLECTED LIGHT LEVELS.
• USED TO SCAN QUESTIONNAIRE, SURVEY REPORTS ETC.

22. OBR
OPTICAL BARCODE READER

23. • DATA CODED IN THE FORM OF SMALL LINES (BARS) CALLED BAR CODES.
• BAR CODES REPRESENT ALPHANUMERIC DATA BY A COMBINATION OF ADJACENT
VERTICAL LINES (BARS) BY VARYING THEIR WIDTH AND SPACING BETWEEN THEM.
• AND A BAR CODE READER IS A DEVICE TO READ THIS DATA.
• IT CAN BE EITHER A HAND HELD DIVICE OR A STATIONARY SCANNER.

24. MICR

25. • SIMILAR TO OCR
• BANKING INDUSTRY USES IT FOR FASTER
PROCESSING OF LARGE VOLUME OF CHEQUES.
• THE CHARACTERS ON THE CHEQUES ARE PRE-
PRINTED USING A SPECIAL INK HAVING MAGNETIC
PROPERTY.
• THESE NUMBERS ARE IDENTIFICATION CODE,
ACCOUNT NO. AND CHEQUE NO. IN THE ENCODED
FORM.
•

26. VOICE RECOGNITION
• IT IS A DEVICE TO RECOGNIZE THE WORD .
• MOSTLY USED IN ONLINE DICTIONARY.
• LESS POPULAR DUE TO DIFFERENT ACCENT.

27. OUTPUT DEVICES
• THERE ARE 5 TYPE OF OUTPUT DEVICES:-
• 1. MONITOR
• PRINTER
• PLOTTER
• SCREEN IMAGE PROJECTOR
• VOICE RESPONSE SYSTEM

28. OUTPUT DEVICES
• Used by computer to show the produced results of processing.
• Output is devided into two general categories:-
1. Understand and used by human being
2. Output to secondary storage device which can be use further
processing.
Output understood by human can be in the form of
1. Soft copy
2. Hard copy

29.  Soft copy – soft copy is usually a transient form of output and it lost when
computer is turned off.
Types of soft copy—
Monitor
Projector
Speaker
 Hard copy – hardcopy is input on paper and can be read immediately or
store to read later.
Types of hard copy-
Printer
Plotter

30. MONITOR

31. MONITOR
• Monitor is the most common output device which displays
output on the screen monitor are off following types—
1. Gray scale
2. Color monitor
CRT (Cathode ray tube)
LCD (Liquid crystal display) / TFT (Thin film transistor)
LED (Light Emitting Diode)

32. PRINTERS
• A printer produced an output usually in the form of paper.
• This is a primary output device used to prepare permanent document used to human readable
form.
Classification of printer-
1. Impact printer-
Dot matrix printer
Drum printer
Chain printer
1. Non impact printer-
Inkjet printer
Laser printer

33. IMPACT PRINTER
•In impact printer a metallic hammer or a print
head strikes on paper and ribbon to print
characters, that is put pressure on the paper for
printing.

34. DOT MATRIX PRINTER

35. DOT MATRIX PRINTER
 Character printer
 Pattern of dots
 30 to 600 cahracters per second
 Horizontally printed
 Per page printing cost less
 Loud noise
 Few colors
Dot matrix printer has a prind head that moves horizontally (left to right and right to
left across the paper).
The printer which moves in both direction and print the data called by- directional
printing.

36. •Print head contains an array (series) of pins that can
be activated independent of each other to strike
against an inked ribbon to form pattern of data on
the paper.
•To print a character the printer activated the
appropriate set of pins as the print head moves
horizontally.

37. DRUM PRINTER

38. DRUM PRINTER
• One line at a time
• 300 to 2000 lines per min.
• Drum printer are line printers that print an entire line at a time.
• It consist of solid cylindrical drum with characters embossed on its
surface in the form of circular band.
• Each band consist of all the printing cahracters.
• Drum printers are noisy in opertions often use a cover to reduce the
noise level.

39. •The printer has a hammers one opposite each band in a
manner that ink ribbon and paper can be placed
between hammer and drum.
•One each line all the a’s are printed first then all the b’s
and so on until the entire line is comleted.

40. CHAIN PRINTER

41. CHAIN PRINTER
• It uses a chain of print characters rapped around 2 pullays like drum
printer.
• There is one set of hammers
• Circuit inside the printer detects when the correct character appears at
the desired print positions on the page.
• The hammer then strikes the page pressing against the ribbon and the
character located at the desired print positions and impression of the
character is left on the page.
• The chain keep rotating until all the required print position online
have been fill then the page moves to up to print the next line.

42. NON IMPACT
PRINTERS

43. INKJET PRINTER

44. INKJET PRINTERS
• 64 tinny nozzels.
• Inkjet printer are character printer that form character and all kind of images by
spraying small drops of ink on paper.
• The print head of inkjet printer contains upto 64 tinny nozzeles that can be
heated up selectively in few micro seconds by a integrated circuits.
• When the circuit heats up, the ink near it vaporises and is ejected through the
nozzels making a dot on the paper placed in front of print head.
• The printing character , the printer selectively heats the appropriate set of
nozzeles as the print head moves horizontally.
• Per page printing cost is less.
• Quiter than dot matrix printer

45. LASER PRINTER

46. LASER PRINTER
• Laser printer are page printer that print one page at a time.
• Laser printer produce very high quality output because they
form characters by very tiny ink particles.
• Laser printer are faster in printing speed than other printers.
• Used from 1970’s from mainframe computer and by 1980’s
also used for micro computers.
• Many laser printer also include additional processor, RAM
and ROM

47. PLOTTERS
• A plotter produces drawing using pens that are attached to a movable arm.
• High quality bar graphs, pie charts with a plotter gives a good quality
output.
• Although dot matrix, inkjet, laser printer are capable of producing graphics
output but many engineering designs applications like architectural plan of a
building, design of a mechanical component of car or air craft.
• Often required high quality graphics, output on large printer are not suitable
for such application than special type of output device used for this purpose
called plotter.

48. DRUM PLOTTER

49. DRUM PLOTTER
•It is a pen type structure which moves on paper surface to draw
a graphics. A paper role along by the drum and this pen draws
graphics under the control of computer.
•Color presentation of plotter is excellent.
•Plotters generally used fiber tipped pen but when high quality
is desire than than technical drafting pen is used which is
capable of drawing a line equal to thousand part of an inch.
•A plotter drawings with a rate of few inches per second.

50. FLATBED PLOTTER

51. FLATBED PLOTTER
• SAME AS DRUM PLOTTER EXCEPT POINT 2.
• HERE PAPER IS STABLE NON MOVABLE BED OR
TRAY.

52. MICROFILM
• MICROFILM READER IS A DEVICE USED FOR READING OF DOCUMENTS STORED
AS MICROFORM. MICROFORM INCLUDES FLAT FILM, MICROFILM, APERTURE CARDS,
MICROFICHE, AND ULTRA FICHE.
• USING OPEN REELS OR CASSETTES, MICROFILM IS OFTEN USED AS A WAY TO STORE
MANY DOCUMENTS IN A SMALL SPACE.
• IT HAS BECOME INCREASINGLY IMPORTANT IN THE DEVELOPMENT OF FILMS AS WELL
AS STORAGE OF ARCHIVED NEWSPAPERS.
• WITH THE ADVENT OF MICROFILM, NATURALLY WOULD FOLLOW THE DEVELOPMENT OF
MICROFILM READERS.
• A MICROFILM READER IS USED IN PROJECTING AND VIEWING TO MAGNIFY MICROFILM
IMAGES TO READABLE PROPORTIONS.
• WITH THE INCREASING POPULARITY OF COMPUTERS, MICROFORM HAS DECREASED IN
USE ALTHOUGH MANY LIBRARY ARCHIVES STILL REMAIN IN MICROFORM.

53. MICROFICHE
• A MICROFICHE IS A CARD MADE OF TRANSPARENT FILM USED TO STORE
PRINTED INFORMATION IN MINIATURIZED FORM.
• TO READ THE CARD, A USER PLACES IT UNDER THE LENS OF A READER
MACHINE, WHICH MAGNIFIES IT GREATLY.
• THE THINNESS AND SMALL SIZE OF THE FILM ENABLES IT TO BE STORED
VERY EASILY AND EFFICIENTLY, ALLOWING LIBRARIES, MUSEUMS AND
BUSINESSES TO INCREASE THEIR RESOURCE COLLECTIONS WITHOUT THE
NEED FOR ADDITIONAL STORAGE SPACE.
• WHILE MANY ORGANIZATIONS STORE RECORDS DIGITALLY, MICROFICHE
RECORDS ARE STILL CREATED AND USED AND, IN FACT, HAVE SOME
ADVANTAGES OVER DIGITAL STORAGE OPTIONS, INCLUDING THEIR
POTENTIALLY LONGER LIFESPAN.

54. VOICE RECOGNITION & RESPONSE DEVICE
• VOICE RECOGNITION IS A COMPUTER SOFTWARE PROGRAM OR HARDWARE DEVICE WITH
THE ABILITY TO DECODE THE HUMAN VOICE.
• VOICE RECOGNITION IS COMMONLY USED TO OPERATE A DEVICE, PERFORM COMMANDS,
OR WRITE WITHOUT HAVING TO USE A KEYBOARD, MOUSE, OR PRESS ANY BUTTONS.
• TODAY, THIS IS DONE ON A COMPUTER WITH AUTOMATIC SPEECH RECOGNITION (ASR)
SOFTWARE PROGRAMS.
• MANY ASR PROGRAMS REQUIRE THE USER TO "TRAIN" THE ASR PROGRAM TO
RECOGNIZE THEIR VOICE SO THAT IT CAN MORE ACCURATELY CONVERT THE SPEECH TO
TEXT.
• FOR EXAMPLE, YOU COULD SAY "OPEN INTERNET" AND THE COMPUTER WOULD OPEN
THE INTERNET BROWSER.