CHAPTER 5
INPUT
WHAT IS INPUT: Entering data, programs, commands, and user responses into the computer
1. Data - raw facts in text, numbers, images, audio, and video.
2. Programs - stored instructions that direct the computer
3. Commands - keywords and phrases that direct the computer
4. User responses - responses to questions or messages from the software
THE KEYBOARD
1. Typing area, numeric keypad, function keys, key combinations.
2. Other types of KB: Cordless keyboard, and ergonomic keyboard.
POINTING DEVICES: controls movement of pointer.
1. Mechanical Mouse: a rubber or metal ball control the direction of pointer movement
2. Optical mouse: it emits and senses light to detect mouse’s movement
3. Cordless mouse: battery-powered, uses radio waves or infrared light to transmit data to the system
4. Mouse operations: point, click, right-click, double-click, triple-click, drag, right-drag, rotate wheel, press wheel
button.
5. Other pointing devices: trackball, touchpad, pointing stick, joystick and wheel, light pen, touch screen, stylus.
VOICE INPUT: the process of entering data by speaking to a microphone
1. Voice recognition/speech recognition
2. Speaker-dependent software or speaker independent software
AUDIO INPUT: the process of entering any sound, like speech, music, sound effects, into a computer
1. MIDI: musical instrument digital interface
VIDEO INPUT: the process of capturing full-motion images into a computer and storing them on a storage medium.
1. Video capture cared: convert analog video signal to digital signals
2. Digital video camera: records video as digital signals, UBS and Firewire may be used for uploading to computer
3. PC Video cameras and Web cams
4. Video conferencing
SCANNERS AND READING DEVICES
1. Scanner: light-sensing device that reads printed text and graphics
2. Optical reader: device that uses light source to read characters, codes and convert them to digital signals.
a. OCR: optical character recognition
b. OMR: optical mark recognition, in
c. Bar code reader: read bar code, as in supermarkets, UPC: Universal Product Code
3. Turnaround documents: returned back to sender, utility companies. Contain OCR characters
4. MICR: magnetic-ink character recognition: printed in magnetized ink, exclusively used in banking industry
TERMINALS
1. Display terminals, or video display terminals (VDTs) = keyboard + screen
2. Dumb terminals
3. Intelligent terminals (programmable terminals, smart terminals)
4. Special-purpose terminals (Point-of-sale (POS) terminals)
BIOMETIRIC INPUT: authenticates person’s identity.
1. Fingerprint scanner
2. Hand geometry system
3. Voice verification system
4. Signature verification system
5. Iris recognition systems: read patterns in the iris of the eye.