A device or piece of hardware that enables us to print text or illustrations on paper. There are many different types of printers. In terms of the technology utilized, printers fall into the following categories: Daisy wheel: Similar to a ball-head typewriter, this type of printer has a plastic or metal wheel on which the shape of each character stands stands out in relief. A hammer presses the wheel against a ribbon, which in turn makes an ink stain in the shape of the character on the paper. Daisy-wheel printers produce letter-quality print but cannot print graphics
Dot-Matrix: Creates characters by striking pins against an ink ribbon. Each pin makes a dot and combinations of dots form characters and illustrations. Ink jet: Sprays ink at a sheet of paper. Ink-jet printers produce high- quality text and graphics Laser : Uses the same technology as copy machines. Laser printers produce very high quality text and graphics. LED+LCD: Similar to a laser printer, but uses liquid crystals or light- emitting diodes rather than a laser to produce an image on the drum. Line Printer: Contains a chain of characters or pins that print an entire line at one time. Line printers are very fast, but produce low- quality print. Thermal Printer: An inexpensive printer that works by pushing heated pins against heat-sensitive paper. Thermal printers are widely used in calculators and fax machines
Monitors Another term for display screen. The term monitor, however, usually refers to the entire box, whereas display screen can mean just the screen. There are many ways to classify monitors. The most basic is in terms of color capabilities, which separates monitors into three classes: Monochrome: Monochrome monitors actually display two colors, one for the background and one for the foreground the colors can be black and white, green and black, or amber and black. Gray Scale: A gray-scale monitor is a special type of monochrome monitor capable of displaying different shades of gray Colour Monitors: can display anywhere from 16 to over 1 million different colors. Color monitors are sometimes called RGB monitors because they accept three separate signals -- red, green, and blue.
Speakers Is a form of output from a computer that is an electro acoustic transducer that converts electrical signals into sounds loud enough to be heard at a distance. Also referred to as loud speakers
Projector A projector is any device which creates a light- projected image by shining a light through a small, transparent image. In order to refine this image, projectors must also employ lenses in order to focus the light. Projectors can transform a very small image into a large one because the image which is projected will be the same size as the pool of light created by the light source behind the transparent image. There are many different kinds of projectors, but they work on the same basic principle. One of the more complicated of the commonly known projectors is the movie projector.
RELATED VIDEOS: If you want to find out more about how they work here are some links to YouTube videos: Printers: Monitors: Speakers:
Sources: How Does a Projector Work? | eHow.com work.html#ixzz1aaahOOoH How Does a Projector Work? | eHow.com work.html#ixzz1aaahOOoH