1. Chapter 5 Input and Output: The User Connection

2. Input n input device - hardware device that translates raw data into a format understandable by the computer n popular examples –keyboard –pointing devices - mouse, touchpad, trackball, joystick, touch screen, etc.

3. Other input examples n optical recognition - collects data at the source (no keying) –scanner - converts text and/or visual images into a computer understandable format –other examples magnetic-ink character recognition, optical character recognition, Universal Product Code n speech recognition - generally must be trained for each user n digital cameras

4. Output n output device - hardware device designed to translate what is stored in the computer to some human recognizable form n popular examples –screen (monitor) - produces soft copy (temporary) output –printer - produces hard copy (tangible) output

5. Screen (Monitor) n CRT –image made up of individual dots called pixels (picture elements) –resolution of image (clarity) directly related to number of pixels n flat-panel - uses LCD technology –used for laptops, but also moving into desktop market –2 basic technologies active-matrix (TFT) passive-matrix

6. Printers n impact printer - some type of physical contact is used to produce an image –speed rather than quality usually emphasized –examples: line printers, dot-matrix printers n non-impact printer - image is produced without touching the page –laser - use a technology similar to photocopiers very high quality output –ink-jet - sprays ink from jet nozzles not quite as fast or high quality as laser printers

7. Audio Output n voice output –speech synthesis n music output and other sounds –often used with multimedia applications –MIDI (musical instrument digital interface) - set of rules for connecting devices that produce digital music

8. Combining I/O n Terminal - a device that combines both input and output capabilities –dumb terminal - basically a keyboard and monitor –POS terminal - supermarket checkout bar code reader is main input device screen and printer provide output

9. Ethical issues about data n once data is in a computer it can be –used –altered –sold –shared n quite easily - for both acceptable and unacceptable purposes