[email protected] 071-8221172. data- row facts information - convert to more useful &...

[email protected] 071-8221172


Data- row facts Information - convert to more useful & meaningful form

Data processing is just like making a cake


Data InformationProcess

Data (row facts)Numbers, words, image, soundEg: List of my friends

Information (Processed data or data has been convert to more useful & meaningful formEg: list can arrange in ascending order (A to Z )


Input OutputProcess

Input Devisers Output Devisers

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Data / Instructions

Command /Signal Flow

Block diagramOf computer System


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


Keyboard

Convert letters, numbers and other characters into electronic signals

• 1.Typing keys• 2.Numeric keypad• 3.Function keys• 4.Control keys

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



Mouse

• Pointing device

1.Ball underneath rolls

2.Laser to sense the motion


PS 2 Mouse

USB Mouse


Light pen

Pointing device• Light sensitive pen

like devise ( help to draw )


Digital Camera

• No film roll• Capturing videos• Photos can directly

move into the

computer without scanning


Scanner

• Convert text, drawing, photos in to digital form that can

• Stored and edit in computer


Joy stick

• Joy stick (Pointing device)

• Pointing devise • Help to play video

games


Fingerprint scanner

Pointing device• Use to scene finger prints for

security reasons , or time attendance


Touch screen (Pointing device)

Display screen that receives input

• from the touch of a finger( ATM screens in banks)

• (Input and output both)


Magnetic strip reader

• Used as credit card, railway tickets,

• time attendance, debit cards

trackball



Magnetic Ink Character Recognition, (MICR)

• MICR codes can be easily read Cheque

numbers


Optical character recognition,(OCR)

• Optical character recognition, conversion of images of text into characters


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

barcode reader (or barcode scanner)



Graphic tablets (Pointing device)

• Like electronic tracing paper

• Use for CAD


Microphone

• Input sound


OUTPUT DEVICES


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.


MONITOR

Cathode ray tubes (CRTs) Liquid crystal displays

(LCDs)


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

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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.)


Speakers and head phones

• Taking sound out of the computer

• Some computer displays have rather basic speakers built-in.

• Laptops come with integrated speakers

impact vs non impact printer


daisywheel

• http://www.youtube.com/watch?v=CTBM9JELUYQ

• Daisy wheel printing is an impact printing technology invented in 1969



Dot-Matrix printer

• Less expensive• Noisy• Producing the image

by striking paper through the ribbon

• Low quality print out

• Very slow


Ink Jet-printer

• Cheaper than laser• Not that noisy• Technology-ink flowing

through the appropriate nozzles.

• Quality than dot matrix

• Faster than dot matrix


Laser-printer

• Expensive• Very silent in

operation• Work with toners

• Very High quality print outs

• Very fast

plotter


projector, a device that projects an image

on a surface.



SECONDARY STORAGE

• Hard Disk

• Floppy Disk

• Optical Disk Storage

• Magnetic tape


Hard Disk

• non-volatile storage device which stores digitally encoded data on rapidly rotating platters with magnetic surfaces


Hard Disk


Floppy Disk


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


Zip Disks

• Zip disk 100-750Mb

• better than floppy

• portable and removable

• An outdated medium


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


DVD

Digital Versatile Disk (DVD)


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 )


Main memory


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


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


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


Computer Ports


PS/2 connector

A mini DIN plug containing 6 pins. Developed by IBM for connecting the keyboard (purple ) and mouse (green )

Shape -Round


Parallel port

connector for scanners and printers

The 25-pin port


Serial Port

A 9-pin D-type connector meeting EIA-232 standard. Possibly used to connect some trackballs, mice, modems and monitors.


VGA port

the 15-pin plugs and sockets that connect the computer to the monitor.

used to connect a monitor


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

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. [email protected]

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Ethernet (or Network) Port

used to connect with internet /network


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.


Software


software

• collection of computer programs, procedures and documentation that perform some tasks on a computer system.


Hardware

System Software

Application Software

USER


Application Software

• examples of software applications are word processors, spreadsheets, and media players, database applications.


System software

• System software such as operating systems, which interface with hardware to provide the necessary services for application software,

[email protected] 071-8221172. data- row facts information - convert to more useful &...

Documents

data row factsinformation

keyboard layoutthe

left letter row

magnetic strip readerused

devicepointing devise

useful meaningful formeg

scene finger

input deviseskeyboard