Input
- It is any data and instructions entered into the memory of a computer- Instructions can be entered into the computer in the form of programs, commands and user responses
- 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
- User responses is an instruction a user issues by replying to a question displayed by a program
Input Devices
- It is any hardware component that allows users to enter data and instructions into a computerKeyboard
- It is an input device that contains keys users press to enter data and instructions into a computer- Most keyboards have:
- 101 - 105 keys
- A numeric keypad on right side
- Function (fn) key
- CTRL keys
- ALT keys
- Arrow keys
- WINDOWS key
- APPLICATION key
- Toggle key
- 2 types of keyboards:
- Wired keyboards (USB)
- Wireless keyboards (Bluetooth / IrDA)
- Ergonomics incorporates comfort, efficiency and safety into the design of the workplace
- Some phones have predictive text input, which saves time when entering text using the phone's keypad
Pointing Devices
- It is an input device that allows a user to control a pointer on the screenPointer
- It is a small symbol on the screen whose location and shape change as a user moves a pointing deviceMouse
- It is a pointing device that fits under the palm of your hand comfortably- It can be wired or wireless
Other Pointing devices
- Trackball, a stationary pointing device with a ball on its top or side
- Touchpad, a pointing device that is sensitive to pressure and motion
- Pointing stick, a pressure-sensitive pointing device shaped like a pencil eraser that is positioned between keys on a keyboard
Touchscreen and Touch-Sensitive Pads
- Touchscreen is a touch-sensitive display device. Eg: Tablet, touch screen pc, smartphones, ATM machine- Touch-sensitive pad
Pen Input
- With pen input, touch a stylus or digital pen on a touchscreen or graphics tablet to write, draw or make selectionsGame Controllers
- It is the input device that directs movements and actions of on-screen objects in video games and computer games- Eg: Gamepads, joysticks, wheels, light guns, dance pads, motion-sensing controllers
Digital Cameras
- It is a mobile device that allows users to take pictures and store them digitally- Eg: Studio cameras, field cameras, point-and-shoot camera
- 2 factors affect the quality of digital camera photos:
- Resolution - the number of horizontal and vertical pixels in a display device. Pixel is the smallest element in an electronic display
- Number of bits stored in each pixel - 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
Voice Input
- It is the process of entering input by speaking into a microphone- Voice recognition is the computer's capability of distinguishing spoken words
- Audio input is the process of entering any sound into the computer. Eg: Speech, music, sound effects
- Music production software allows users to record, compose, mix and edit music and sounds
Video Input
- It is the process of capturing full-motion images and storing them on a computer's storage medium- How to input video:
- Step 1: Record the video on a digital video (DV) camera or use a video capture card to convert analog signals to digital
- Step 2: Connect the camera to a port on the system unit
- Step 3: Transfer video and images
- 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 calls
Scanner and reading Devices
- Types of scanners:- Flatbed
- Pen or handheld
- Sheet-fed
- Drum
- Optical character recognition (OCR) involves reading characters from ordinary documents
- Turnaround document is a document you return to the company that creates and sends it
- Optical mark recognition (OMR) reads hand-drawn mark such as small circles or rectangles
- An OMR device scans the documents and matches the patterns of light
- A barcode reader, aka barcode scanner uses laser beams to read barcodes
- Radio frequency identification (RFID) uses radio signals to communicate with a tag placed in or attached to an object
- A RFID reader reads information on the tag via radio waves
- RFID can:
- Track times of a runners in a marathon
- Track location of soldiers
- Track employee wardrobes
- Track airline baggage
- Checking lift tickets of skiers
- Manage inventory
- Gauge pressure and temperature of tires
- Check out library books
- Track toll payments
- Credit cards
- Entertainment cards
- Bank cards
- Magnetic ink character recognition (MICR) devices read text printed with magnetised ink
- An MICR reader converts MICR characters into a form the computer can process- Banking industry uses MICR for check processing
- Data collection devices obtain data directly at the location where the transaction or event takes place
- It is used in:
- Restaurants
- Grocery stores
- Factories
- Warehouses
- The outdoors
Biometric Input
- Biometrics authenticates a person's identity by verifying a personal characteristic- Eg: Fingerprint reader, face recognition system, hand geometry system, voice verification system, signature verification system, iris recognition system, retinal scanners
Terminals
- A terminal is a computer that allows users to send data to and/or receive information form a host computer- Eg:
- POS terminal - Records purchases, processes payment and updates inventory
- Automated teller machine (ATM) - Allows users to access their bank accounts
- DVD kiosk - A self-service DVD rental machine
Input Devices for Physically Challenged Users
- Several input devices are available to assist physically challenged users.- Eg: Keyguard, keyboards with larger keys, on-screen keyboard, various pointing devices, head-mounted pointer, gesture recognition, computerized implant devices
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