Input Devises Keyboard Mouse Light pen Digital Camera

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 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 arosha_g@yahoo. com 071 -8221172

QWERTY /ˈkwɜrti/ is the most common modernday 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-RT-Y. The QWERTY design is based on a layout created for the Sholes and Glidden typewriter and sold to Remington in 1873. arosha_g@yahoo. com 071 -8221172

Mouse • Pointing device 1. Ball underneath rolls 2. Laser to sense the motion arosha_g@yahoo. com 071 -8221172

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

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

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

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

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

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

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

trackball arosha_g@yahoo. com 071 -8221172

Magnetic Ink Character Recognition, (MICR) • MICR codes can be easily read Cheque numbers arosha_g@yahoo. com 071 -8221172

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

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

Graphic tablets (Pointing device) • Like electronic tracing paper • Use for CAD arosha_g@yahoo. com 071 -8221172

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

OUTPUT DEVICES arosha_g@yahoo. com 071 -8221172

OUTPUT DEVICES 1. Soft copy – Monitor CRT – Projector 2. Hard copy printer impact plotter 3. Sound LCD LED non impact arosha_g@yahoo. com 071 -8221172

RT HVH H Out put Hard copy Soft copy monitor LCD KGHVH JVH Projector LED arosha_g@yahoo. com 071 -8221172 Sound PLOTTER

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. arosha_g@yahoo. com 071 -8221172

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

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

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

daisywheel • http: //www. youtube • Daisy wheel. com/watch? v=CT printing is an BM 9 JELUYQ impact printing technology invented in 1969 arosha_g@yahoo. com 071 -8221172

Dot-Matrix printer • Less expensive • Noisy • Producing the image by striking paper through the ribbon • Low quality print out • Very slow 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 arosha_g@yahoo. com 071 -8221172

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

plotter 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 arosha_g@yahoo. com 071 -8221172

SECONDARY STORAGE • • Hard Disk Floppy Disk Optical Disk Storage Magnetic tape arosha_g@yahoo. com 071 -8221172

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

Hard Disk arosha_g@yahoo. com 071 -8221172

Floppy Disk 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 arosha_g@yahoo. com 071 -8221172

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

Optical Disk Storage • CD- 650 -700 MB • DVD-2 GB-8 GB • 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 arosha_g@yahoo. com 071 -8221172

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DVD Digital Versatile Disk (DVD) 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 ) arosha_g@yahoo. com 071 -8221172

Main memory 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 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 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 arosha_g@yahoo. com 071 -8221172

Computer Ports 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 arosha_g@yahoo. com 071 -8221172

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

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

Ethernet (or Network) Port used to connect with internet /network 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. arosha_g@yahoo. com 071 -8221172

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Software arosha_g@yahoo. com 071 -8221172

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

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

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