CHAPTER 7 : INPUT AND OUTPUT

WHAT IS INPUT?

• ·         Input is any data and instructions entered into the memory of a computer
• ·         Commonly used input methods include:

-          Keyboard

-          Pointing devices

-          Touch screen

-          Pen input

-          Motion input

-          Voice input

-          Video input

-          Scanner and reading devices

KEYBOARD

• ·         A keyboard is an input device that contains keys users press to enter data and instructions into a computer or mobile device
• ·         An ergonomic keyboard has a design that reduces the chance of repetitive strain injuries
• ·         Ergonomics incorporates comfort, efficiency, and safety into the design of the workplace

POINTING DEVICES

• ·         A pointer is a small symbol on the screen whose location and shape change as a user move a pointing.
• ·         For example, a mouse is a pointing device that fits under the palm of your hand comfortably
• ·Optical mouse, laser mouse, and touch mouse.

·         Other examples:

-          Touchpad

-          Pointing stick

-          Trackball

PEN INPUT

• ·         With pen input, you touch a stylus or digital pen on a flat surface to write, draw, or make selections
• ·         A graphics tablet, also called a digitizer, is an electronic plastic board that detects and converts movements of a style or digital pen into signals that are sent to the computer

MOTION INPUT

• ·         With motion input, sometimes called gesture recognition, users can guide on-screen elements using air gestures

VOICE INPUT

• ·         Voice input is the process of entering input by speaking into a microphone
• ·         Voice recognition, also called speech recognition, is the computer or mobile device’s capability of distinguishing spoken words

AUDIO INPUT

• ·         Audio input is the process of entering any sound into the computer such as speech, music, and sound effects
• ·         Music production software allows users to record, compose, mix, and edit music and sounds

VIDEO INPUT

• ·         Video input is the process of capturing full-motion images and storing them on a computer or mobile device’s storage medium
• ·         A webcam is a type of digital video (DV) camera.

SCANNER AND READING DEVICES

• ·         A scanner is a light-sensing input device that reads printed text and graphics and then translates the results into a form the computer can process
• ·         An optical reader is a device that uses a light source to read characters,  marks, and codes and then converts them into digital data that a computer can process

-          Optical character recognition (OCR)

-          Optical mark recognition (OMR)

• ·         A bar code reader, also called a bar code scanner uses laser beams to read bar codes
• ·         A QR code stores information in both a vertical and horizontal direction
• ·         Magstripe readers read the magnetic stripe on the back of cards such as:

-          Identification card

-          Bank card

-          Credit card

WHAT IS OUTPUT?

·         Output is data that has been processed into a useful form

·         Examples:

-          Displays

-          Printer

DISPLAYS

• ·         A display visually conveys text, graphics, and video information
• ·         A monitor is a display that is packaged as a separate peripheral device

-          LCD monitor

• ·         Today’s monitors use a digital signal to produce a picture
• ·         To display the highest quality images, the monitor should plug into:

-          A DVI port

-          An HDMI port

-          A Display Port

• ·         Home users sometimes use a digital television (DTV) as a display
• ·         HDTV is the most advanced form of digital television
• ·         A Smart TV is an Internet-enabled HDTV

  PRINTER

• ·         A printer produces text and graphics on a physical medium
• ·         A nonimpact printer forms characters and graphics on a piece of paper without actually contacting the paper
• ·         An ink-jet printer forms characters and graphics by spraying tiny drops of liquid ink onto a piece of paper

-          Color or black-and-white

-          Speed is measured by the number of pages per minute (ppm) it can print

• ·         An all-in-one printer is a single device that prints, scans, copies, and in some cases, faxes
• ·     Sometimes called a multifunction printer

• ·         A thermal printer generates images by pushing electrically heated pins against the heat-sensitive paper
• ·         A mobile printer is a small, lightweight, battery-powered printer that allows a mobile user to print from a mobile device
• ·         A label printer is a small printer that prints on an adhesive-type material that can be placed on a variety of items
• ·         Impact printers form characters and graphics on a piece of paper by striking a mechanism against an inked ribbon that physically contacts the paper

OTHER OUTPUT DEVICES

• ·       Many users attach surround sound speakers or speaker systems to their computers, game consoles, and mobile devices to generate higher-quality sounds
• ·         Headphones are speakers that cover or are placed outside of the ear
• ·         Earbuds (also called earphones) rest inside the ear canal
• ·         A data projector is a device that takes the text and images displaying on a computer or mobile device screen and projects them on a larger screen
• ·         Joysticks, wheels, gamepads, and motion-sensing game controllers can be considered output devices when they include force feedback
•  Technology that sends resistance to the device in response to actions of the user