InputBy Hollee Smalley

What is Input?

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

What are input devices?

• An input device is any hardware component that allows users to enter data or instructions.

• Popular input devices include: the keyboard, mouse, stylus, digital pen, microphone, digital camera, and scanner.

The keyboard

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

• Computer keyboards have a typing area that includes letters of the alphabet, numbers, punctuation marks, and other basic keys.

• Function keys are programmed to issue commands.

Keyboard connections

• Desktop computer keyboards are usually attached via a cable to a small serial port.

• A cordless keyboard is a battery powered device that transmits data using wireless technology, such as radio waves or infrared light waves.

Keyboard Ergonomics

• An ergonomic keyboard has a design that reduces the chance of wrist and hand injuries.

• The goal of ergonomics is to incorporate comfort, efficiency, and safety into the design of the items in the workplace.

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 the user moves a pointing device.

Pointing devices cont.

• A mouse is a pointing device that allows users to control the movement of the pointer. It is the most widely used pointing device on the desktop computer.– A mechanical mouse translates the movement of a ball

in its underside into signals the computer can process,– An optical mouse uses devices that emit and sense light

to detect the mouse’s movement.– A cordless mouse transmits data using wireless

technology.

Other pointing devices

• A trackball is a stationary device with a ball that one rotates to move the pointer.

• A touch pad is a flat, pressure-sensitive device that you slide your finger across to move the pointer.

• A pointing stick is a device positioned on the keyboard that you push to move the pointer.

Other pointing devices cont.

• A joystick is a steering wheel type device that you turn to stimulate driving a vehicle.

• A light pen is a light-sensitive device that you press at the screen to select an object.

• A touch screen is a touch-sensitive display device that you interact with by touching areas if the screen.

• A stylus or digital pen uses pressure to write text and draw lines.

Voice input

• Voice input is the process of entering data by speaking into a microphone.

• Voice recognition is the computer’s capability of distinguishing spoken words.

• Most voice recording programs are a combination of speaker-dependent software, which makes a profile of your voice, and speaker-independent software, which has a built-in set of word patterns.

Audio input

• Audio input is the process of entering any sound into the computer such as speech, music, and sound effects.

Input devices for mobile users

• The primary input device for a PDA is a basic stylus.

• The primary for a tablet PC is a digital pen, with which you can write on the device’s screen.

Digital cameras

• A digital camera allows users to take pictures and store the photographed images digitally.

• Resolution describes the sharpness and clearness of an image.

• The image is downloaded to a computer’s hard disk via cable or copied from the camera’s storage media.

Video input

• Video input is the process of capturing full-motion images into a computer and storing them onto a storage medium, like a hard drive.– A PC video camera enables users to capture

video and still images and then send or broadcast the images over the internet.

– A web cam displays its output on a web page.

Scanners and reading devices

• A scanner is a light-sensitive input device that reads printed text and graphics and translates the results into a form the computer can process.– A flat-bed scanner works like a copy machine

except it creates a file of the document.– An optical reader uses a light to read marks and

codes and converts them into digital data.

Data collection devices

• Data collection devices obtain data directly at the location where the transaction or event takes place.

• Data collection devices are used in factories or warehouses, anywhere cleanliness is not easily controlled.

Terminals

• A terminal consists of a keyboard, monitor, video card, and a memory.

• Terminals have three basic categories:– Dumb terminal-has no processing power, therefore,

cannot function as an independent device.– Smart terminal- has a processor, giving it the capability

of performing some functions independent of the host computer.

– Special-purpose terminal- perform specific tasks and contain features uniquely designed for use in a specific industry.

Biometric input

• A biometric device translates a personal characteristic into digital code that is compared with a digital code stored in the computer to identify an individual. – Fingerprint scanner- captures curves and indentations

of a fingerprint.– Face recognition system- capture a live face image.– Voice verification- compares live speech with a stored

voice pattern,– Iris recognition system- reads patterns in the iris of the

eye.

Input devices for the physically challenged users

• The Americans with Disabilities Act requires any company with 15 or more employees to make reasonable attempts to accommodate the needs of physically challenged workers.

• Some example to help those who are physically challenged:– Voice recognition– On-screen keyboards– Keyguards- allows one to rest hands on the keyboard

without accidentally pressing any keys.