Input 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.
An input device is any hardware component that allows users to enter data and instructions into a computer.
KEYBOARD
A keyboard is an input device that contains keys users press to enter data and instructions into a computer .
The insertion point, also known as the cursor is a symbol on the screen that indicates where the next character you type will appear.
An ergonomic keyboard has a design that reduces the chance of wrist and hand injuries.
Ergonomic incorporates comfort , efficiency, and safety into the design of the workplace.
Keyboard on mobile devices typically are smaller , Some phones have predictive text input , which saves time when entering text using the phone's keypad.
POINTING DEVICES
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.
MOUSE
A mouse is a pointing device that fits under the palm of your hand comfortably. -mostly widely used pointing device on desktop computers.
A mouse can be wired or wireless.
A trackball is a stationary pointing device with a ball on its top or side.
A touchpad is a small, flat, recangular, pointing device that is sensitive to pressure and motion.
A pointing stick is pressure sensitive pointing device shaped like pencil eraser that is positioned between keys on a keyboard.
Touch Screens and Touch- Sensitive Pads
A touch screen is a touch-sensitive display device.
With Pen input , you touch a stylus or digital pen on a flat surface to write m draw, or make selections.
GAME CONTROLLERS
Video games and computer games use a game controller as the input device that directs movements and actions of on-screen objects. - Gamepads, Joysticks and wheel , light gun , dance pad .
Digital Cameras
A digital camera is a mobile device that allows users to take pictures and store them digitally .
- Studio cameras , Field cameras , point and shoot camera .
Two factors affect the quality of digiral camera photos:
Resolution: the number of horizontal and vertical pixel in a display device and 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 represent a pixel , the more colors and shades of gray that can be represented.
Voice input
Voice input is the process of entering input by speaking into a microphone.
Voice recognition is the computer's capabablity of distinguishing spoken words.
Audio input is the process of entering any sound into the computer .
Video Input
Video input is the process of capturing full motion images and storing them on a computer's storage medium.
A webcam is type of digital video camera that enables a user to:
-Capture video and still images
-Send e-mail message with video attachments
-Add live images to instant messages
-Broadcast live images over the internet
-Make video telephone calls
A video conference is a meeting between two or more geographically separated people .
Scanners and Reading Devices
Optical character recognition (OCR) involves reading characters from ordinary documents.
A turnaround documents is a document you return to the company that creates and sends it.
Optical mark recognition (OMR) reads hand-drawn mark suck as small circles or reactangles.
An OMR device scans the documents and mathces the patterns of light.
A bar code reader also called a bar code scanner use laser beams to read bar codes.
RFID ( radio frequency identification) uses radio signals to communicate with a tag placed in or attached to an object.
An RFID reader reads information on the tag via radio waves
RFID can track : location of soldiers , times of runners in a marathon ,employee wardrobes , airline baggage.tracking toll payments .
Magnetic stripe card readers read the magnetic stripe on the back of cards such as :
-Credit cards
-Entertaiment cards
-Bank cards
-Other similar cards
MICR ( MAGNETIC INK CHARACTER RECOGNITION ) devices read text printed with magnetized 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.
Used in :
-Restaurents
-Grocery Stores
-Warehouse
-Factories
-The outdoors
Biometric INPUT
Biometric authenticates a person's identity by verifying a personal characteristic:
-Fingerprint reader , Face recognition system , Hand geometry system , Voice verification system and more .
Terminals
A terminal is a computer that allows users to send data to and receive information from a host computer.
Pos terminal - record purchases , process, payment and update inventory.
An ATM ( automated teller machine) allows users to access their bank accounts
DVD kiosks- A self service DVD rental machine.
Input devices for Physically challenged users
Several input devices are available to assist physically challenged users:
-Keyguard
-Keyboard with larger keys
-On-screen keyboard
-Various pointing devices
-Head-mounted pointer
-Gesture recognition
-Computerized implant device.
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