Chapter 2: Input Devices

Chapter 2: Input Devices

1. Keyboard

   • Allow for straight forward input of text by pressing buttons.
   • Limited to around 100-115 keys
   • Numeric Keypad: speeds up the entry of numbers
   • Concept keyboard: replacement keys/overlays/different layout
   • Useful for young children

2. Pointing devices

   • Allows objects to be selected and manipulated on the screen
   • Mouse: used to select menus or objects on the screen
   • Track pad: Used on portable computers where there is no space for a mouse
   • Tracker ball: useful for people with unsteady hands and can't hold the mouse still and click at the same time

3. Game devices

   • Joystick: playing games and consists of a stick that can move objects on the screen in 2D and buttons that can perform actions
   • Game pads: include various controls which have different functions depending on the game being played
   • Gesture control
     • Responds to gestures made by users with no physical devices

4. Magnetic stripe and smart chip

   • Magnetic stripe used for payments so that the data on the cad can be read quickly
   • Smart chip contains more data and is more secure requiring the use of a pin to confirm owneership
   • E.g- SIM cards, electronic door keys, credit cards

5. Scanner

   • Used to transfer a 2D image into a file on the computer
   • Hand held scanner: moved around oddly shaped objects. 3D objects or along lengthy documents
   • Fladbed scanner: useful for flat documents, take a image of the page and digitize is so that it can be used by a computer
     • Useful when copying a diagraph so it can be used in a presentation for example
     • Save time when converting hand written notes into text, although, accuracy can be variable
   • Barcode scanners: used to read the data contained in a barcode

6. Optical mark reader

   • Reads marks optically- used for reading national lottery strips for example
   • Read large volumes of data where choice shave been made but they are not suitable if written responses are required

7. Digital camera

   • Digital camera images can be changed on the computer, used as part of documents and presentations, printed or sent electronically to other people.
   • Video cameras can be used but instead of producing still images, they produce moving images that can also be edited, viewed or used as part of a presentation or website.

8. Microphone

   • Used for adding voice-overs to presentations or movies controlling the computer, dictating using voice recognition for example

9. Sensor

   • Can be used when monitoring the environment eg. thermometers

10. Touch Screen

    • Word screen will suggest an output device
    • Ability to detect touch and respond to input based upon the user touching the screen
    • Touch can be used to open applications, enter text using an on-screen keyboard, play games and draw images.