Input Devices

Input DevicesBy: Ganesh1Computer keyboardA keyboard is used for typing in data. The keyboard is used to type text and numbers into aword processor,text editoror other programs.

AdvantageDisadvantageVery ease to use and requires no trainingTyping errors commonly occurCheap to buyTyping for long periods can cause RSIAccuracy of entered text can be checked on screen

2Numeric KeypadsAre used to enter numerical data. For e.g. entering numerical data into a spreadsheet

AdvantagesDisadvantagesVery easy to use and requires no trainingTyping errors commonly occur

3Mice and Tracker ballThey are used to make selections from a graphical user interface such as button, menu or iconMice AdvantagesMice DisadvantagesEnables rapid selection of menu itemsNeed a flat surfaceCheap to buyDifficult to use if you have limited hand movementTracker ball AdvantagesTracker ball DisadvantagesFaster to use and navigateMuch more expensive than mice

4Video DigitizersA video digitizer is used to convert sequences ofanalogueimages into adigitalformat. Thedigitizedimages can then be saved as a file and played back on a monitor to produce a moving image.Software will allow the video to be edited and special effects added, as well as individual still images to be captured and saved.

Advantages:Disadvantages:Digital video is easily edited. Sections can easily be cut and pasted together and digital effects added.

Video files take up a great deal of memory.

The output can be rendered into a wide range of formats ranging from DVD quality down to streaming video suitable for the Internet.

A powerful computer and graphics card is often needed to process video footage.

5JoystickCan be used to play video games and enter text. Ajoystickis aninput deviceconsisting of a stick that pivots on a base. A joystick is the principal control device in thecockpit.

Joy stick advantagesJoy stick disadvantagesProvides rapid control required in simulationVery slow at entering textCan be operated by disabled people by foot

6Touch ScreenAtouch screenis anelectronic visual displaythat the user can control through simple ormulti-touch gesturesby touching the screen with a special stylus/pen and-or one or more fingers.

AdvantagesDisadvantagesVery easy to use without trainingSmall icons can be difficult to selectEasy to use in small spaceAre expensive and easily broken

7Magnetic Strip readerUsed for reading data off credit cards, ID cards and pre-payment cards.

AdvantagesDisadvantagesSwiping in the data is much faster than typing in.Magnetic stripes can easily be copiedIs accurate and thus prevent typing errorsMagnetic stripes can easily be damaged by magnetic fieldsThe magnetic stripe is robust

8Smart Card ReaderA smart card reader is an electronic device that readssmart cardsand can be found in the following forms:Somekeyboardshave a built-in card reader.External devices and internaldrive baycard reader devices exist forpersonal computers(PC).Some laptop models contain a built-in smart card reader and/or utilizeflashupgradeablefirmware.

AdvantagesDisadvantagesMore SecureEasily LostPrevents FraudDouble as an ID Card

9Chip and PIN readersThey are used to read credit or debit cards when making purchases.

AdvantagesDisadvantagesThe storage capacity for data on a chip is much higher than for magnetic stripePeople forget thei PINChips are harder to copy compared to a magnetic stripe thus reducing fraud.People can look when the PIN is entered, and thus obtain it.

10ScannersThey can digitize paper based images of photographs, certificates and art work. Paper based images can be scanned into graphic software for editing.AdvantagesDisadvantagesFaster than typing in dataThe quality of the scanned image may be poor if the resolution is not set high enoughMuch more accurate than typing in the data

11Digital CamerasEncodesdigital imagesandvideosdigitally and stores them for later reproduction.AdvantagesDisadvantagesImages can be edited using graphics softwareThe quality may not be that high due to the limited number of pixelsImages can be shared through social media sites.

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