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 modern-day keyboard layout QWERTY /ˈkwɜrti/ 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 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 2 . Hard copy printer impact non impact Monitor CRT LCD LED Projector 2 . Hard copy printer impact non impact plotter 3. Sound arosha_g@yahoo.com 071-8221172
Out put Soft copy Projector monitor Hard copy Sound PLOTTER CRT LCD LED KGHVHJVH JHGJHYGHJ KGHVHJVH JHGJHYGHJ 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. 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.com/watch?v=CTBM9JELUYQ Daisy wheel printing is an 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 100-750Mb better than floppy portable and removable An outdated medium 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 arosha_g@yahoo.com 071-8221172
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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