CHAPTER IIICHAPTER III

INPUTINPUT

Input

- is any data or instruction you enter into the memory of a computer.

4 Types of Input

1. Data - unorganized facts.2. Programs

- a series of instruction that tells a computer how to perform the task necessary to process data into information.

4 Types of Input3. Command - it is an instruction given to a computer program.4. User Response

- a series of instruction that tells a computer how to perform.

Keyboard Pointing Devices Scanners and Reading Devices Digital Cameras Audio and Video Input

Input Devices

KeyboardOne of the primary input

devices on a computer is the keyboard. You enter data into a computer by pressing the keys on the keyboard. Desktop computer keyboards usually have from 101 to 105 keys, while keyboards for

smaller computers such as laptops contain fewer keys.Keyboard Types

1. QWERTY2. Dvorak Keyboard

QWERTY

A Standard computer keyboard sometimes is called QWERTY keyboard because of the layout of its typing area. Pronounced KWER-tee, this keyboard layout is named after the first six leftmost letters on the top alphabetic line of the keyboard. Because of the way the keys are organized, a QWERTY keyboard might limit your typing speed.

Dvorak

A keyboard with an alternative layout was designed to improve typing speed. Called Dvorak keyboard (pronounced de-VOR-zhak), this type of keyboard places the most frequently typed letters in the middle of the typing area.

Pointing Devices

1. Mouse is the widely used pointing device on desktop computers because it takes full advantage of a graphical user interface. Designed to fit comfortable under the palm of your hand, a mouse is an input device that is used to control the movement of the pointer often called a mouse pointer, on the screen and to make selections from the screen.

Pointing Devices

2. Trackball is a stationary pointing devices with a ball mechanism on its top. The ball mechanism in a larger trackball is about the size of a Ping-Pong ball; some mouse devices also have a small trackball about the size of a marble.

Pointing Devices

3. Touchpad or trackpad is a small, flat, rectangular pointing devices that is sensitive to pressure and motion.4. Stick is a pressure-sensitive pointing device shaped like a pencil eraser that was first developed by IBM for its laptop computers.

Pointing Devices

5. Joystick is a vertical lever mounted on a base. Users running game software such as a driving or flight simulator may prefer to use a joystick as their pointing device.6. Touch Screen a monitor that has a touch-sensitive panel on the screen.

Pointing Devices

7. Light Pen is a handheld input device that contains a light source or can detect light.8. Pen Computing the pen also called a stylus looks like a ballpoint pen but uses an electronic head instead ink. Pen computers use handwriting recognition software that translates

the letters and symbols used in handwriting into character data that the computer can use.

Pointing Devices

9. Graphics Tablet also called a digitizer or digitizing tablet, consist of flat, rectangular, electronic plastic board used to input drawings, sketches, or other graphical data.

Scanners and Reading Devices

1. Optical Scanner is a light-sensing input device that reads printed text and graphics and then translates the results into a form the computer can use.2. Optical Reader is a device that uses a light source to read characters, marks, and codes and then converts them into digital data that can be processed by a computer.

1. Optical Character Recognition (OCR) is a technology that involves reading, typewritten, computer printed, or handwritten characters from ordinary documents and translating the images into a form that the computer can understand.

3 Types of Optical Reader

2. Optical Mark Recognition (OMR) devices are hand - drawn marks such as small circles or rectangles.

3 Types of Optical Reader

3.Bar Code Scanners uses laser beams to read to bar codes.

Digital Cameras

Allows you to take pictures and store the photographed images digitally instead of on traditional film.3 Types of Digital Cameras

1. Studio Cameras2. Field Cameras3. Point-and-Shoot Cameras

1. Studio Cameras is the most expensive and highest quality, and used for professional studio work.

3 Types of Digital Cameras

2. Field Cameras Often used by photojournalists and quite expensive, is a portable camera that has many lenses and other attachments.

3. Point-and-Shoot Cameras is more affordable and lightweight and provides acceptable quality photographic images for the home or small business user.

3 Types of Digital Cameras

Audio and Video Input

Audio Input is the process of entering (recording) music, speech, or sound effects.Speech Recognition is the computer’s capability of distinguishing spoken words.

Audio and Video Input

Video Input is the process of entering a full-motion recording into a computer and storing the video on a hard disk or some other medium.Videoconferencing is a meeting between two or more geographically separated individuals who use a network or the Internet to transmit audio and video data.

The End…Prepare for a Quiz next meeting… Good Luck!