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Your Interactive Guide to the Digital World

Discovering � Computers 2012

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What Is Input?

  • Input is any data and instructions entered into the memory of a computer

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What Is Input?

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  • Instructions can be entered into the computer in the form of programs, commands, and user responses

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A program is a series of related instructions that tells a computer what tasks to perform and how to perform them

Programs respond to commands that a user issues

A user response is an instruction a user issues by replying to a question displayed by a program

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What Are Input Devices

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An input device is any hardware component that allows users to enter data and instructions into a computer

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The Keyboard

  • A keyboard is an input device that contains keys users press to enter data and instructions into a computer

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The Keyboard

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  • Most desktop computer keyboards have…

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Between 101 and 105 keys

A numeric keypad on the right side of the keyboard

Function keys, CTRL keys, ALT keys, and arrow keys

WINDOWS key

APPLICATION key

Toggle keys

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The Keyboard

  • The insertion point, also known as the cursor, is a symbol on the screen that indicates where the next character you type will appear

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The Keyboard

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USB port

Wired Keyboards

Bluetooth

IrDA

Wireless Keyboards

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The Keyboard

  • An ergonomic keyboard has a design that reduces the chance of wrist and hand injuries
  • Ergonomics incorporates comfort, efficiency, and safety into the design of the workplace

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The Keyboard

  • Keyboards on mobile devices typically are smaller and/or have fewer keys
  • Some phones have predictive text input, which saves time when entering text using the phone’s keypad

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Pointing Devices

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A pointing device is an input device that allows a user to control a pointer on the screen

A pointer is a small symbol on the screen whose location and shape change as a user moves a pointing device

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Mouse

  • the mouse is a computer input device used to move a cursor around a screen. The mouse buttons are used to interact with whatever is being pointed at.
  • Most widely used pointing device on desktop computers
  • A mouse can be wired or wireless

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Other Pointing Devices

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Trackball

    • A trackball is a stationary pointing device with a ball on its top or side

Touchpad

    • A touchpad is a small, flat, rectangular pointing device that is sensitive to pressure and motion

Pointing Stick

    • A pointing stick is a pressure-sensitive pointing device shaped like a pencil eraser that is positioned between keys on a keyboard

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Touch Screens and Touch-Sensitive Pads

  • A touch screen is a touch-sensitive display device

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Pen Input

  • With pen input, you touch a stylus or digital pen on a flat surface to write, draw, or make selections

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Game Controllers

  • Video games and computer games use a game controller as the input device that directs movements and actions of on-screen objects

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Gamepads

Joysticks and Wheels

Light guns

Dance pads

Motion-sensing controllers

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Game Controllers

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Digital Cameras

  • A digital camera is a mobile device that allows users to take pictures and store them digitally

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Studio cameras

Field cameras

Point-and-shoot camera

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Digital Cameras

  • Two factors affect the quality of digital camera photos:

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    • Resolution is the number of horizontal and vertical pixels in a display device
    • A pixel is the smallest element in an electronic display

Resolution

    • Each pixel consists of one or more bits of data
    • The more bits used to represent a pixel, the more colors and shades of gray that can be represented

Number of bits stored in each pixel

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Voice Input

  • Voice input is the process of entering input by speaking into a microphone
  • Voice recognition is the computer’s capability of distinguishing spoken words

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Voice Input

  • Audio input is the process of entering any sound into the computer

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Speech

Music

Sound Effects

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Video Input

  • Video input is the process of capturing full-motion images and storing them on a computer’s storage medium

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Record video on a digital video (DV) camera or use a video capture card to convert analog signals to digital

Connect the camera to a port on the system unit

Transfer video and images

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Video Input

  • A Web cam is a type of digital video camera that enables a user to:

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Capture video and still images

Send e-mail messages with video attachments

Add live images to instant messages

Broadcast live images over the Internet

Make video telephone calls

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Video Input

  • A video conference is a meeting between two or more geographically separated people

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Biometric Input

  • Biometrics authenticates a person’s identity by verifying a personal characteristic

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Fingerprint reader

Face recognition system

Hand geometry system

Voice verification system

Signature verification system

Iris recognition system

Retinal scanners

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Biometric Input

Pages 282 – 283

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fingerprint reader

hand geometry system

iris recognition system

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Summary

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Various techniques of entering input

Several commonly used input devices

Keyboard, mouse, and other pointing devices; touch screens, pen input, other input for smart phones, game controllers, digital cameras, voice input, video input, scanners and reading devices, biometric input, and terminals

Input devices for physically challenged users