Std-VII Chapter1 Computer Fundamentals

Std-VII Chapter1 Computer Fundamentals An input device is any hardware device that sends data to a computer, allowing you to interact with and control it. Barcode readers and scanners A BCR (barcode reader)or scanner, also known as a POS (point of sale) scanner is a hardware input device capable of reading a barcode using a laser. It can also print out the details of the product or log information about that product into a database. A perfect example of a barcode reader is a supermarket barcode scanner that reads and logs the price of a product. Optical Character Reader (OCR) OCR is an input device used to read a printed text. OCR scans the text optically, character by character, converts them into a machine readable code, and stores the text on the system memory. OMR Short for optical mark reading or optical mark recognition, OMR is the process of gathering information from human beings by recognizing marks on a document. OMR is accomplished by using a hardware device (scanner) that detects a reflection or limited light transmittance on or through a piece of paper. OMR allows for the processing of hundreds or thousands of documents per hour. For example, students may recall taking tests or surveys where they filled in bubbles on paper (shown right) with a pencil. Once the form had been completed, a teacher or teacher's assistant would feed the cards into a system that grades or gathers information from them. MICR Short for magnetic ink character recognition, MICR is a font capable of recognition using magnetically charged ink. Computers equipped with the right hardware and software can print or read the character printed in such ink. MICR font is commonly used to print checks, deposit slips, mortgage coupons, etc. There are several MICR fonts. Magnetic Card Reader A magnetic card reader is a device that retrieves information from a magnetic card physically proximate to, or swiped through a slot in, the device. The picture is an example of a magnetic card reader and a good example of the type of card reader you would see at most retail stores. Output Devices An output device is any piece of computer hardware equipment which converts information into human-readable form. It can be text, graphics, tactile, audio, and video. Some of the output devices are Visual Display Units (VDU) i.e. a Monitor, Printer, Graphic Output devices, Plotters, Speakers etc. LCD An LCD projector is a type of video projector for displaying video, images or computer data on a screen or other flat surface. It is a modern equivalent of the slide projector or overhead projector. Plotters A plotter is a computer hardware device much like a printer that is used for printing vector graphics. Instead of toner, plotters use a pen, pencil, marker, or another writing tool to draw multiple, continuous lines onto paper rather than a series of dots like a traditional printer. Drum Plotter A drum plotter is a pen plotter that wraps the paper around a drum with a pin feed attachment. The drum then rotates the paper as pens move across it and draw the image. It was the first output device used to print graphics and large engineering drawings. There are two types of drum plotters, external and internal. With an external drum plotter, the paper is wrapped around its external surface, while the internal drum plotter uses a sheet of paper wrapped around its internal surface. Flat-Bed Plotter A flat-bed plotter is a mechanical drafting device used with many CAD programs for designers. The paper remains stationary on a flat surface while a pen moves across it horizontally and vertically. This plotter may use several different pen colors to create the graphics. The size of the graphic is limited to the size of the flat-bed plotter's surface. Inkjet Plotter The inkjet plotter creates an image by spraying small droplets of ink on to paper. A popular choice for advertising agencies and graphic designers, inkjet plotters are used generally for large outputs, such as banners and billboards and large signs often seen along roadsides. They are available in thermal or piezoelectric models. Thermal inkjet plotters use heat to apply droplets of ink, while piezoelectric plotters use charged crystals to apply the ink. Inkjet plotters typically produce better quality graphics than other plotter types. Questions 1. What is a barcode reader and how it works? 2. Write an advantage of OCR technology? 3. What is Plotter? List different types of plotter. 4. What is MICR? 5. What is the roe of output devices? .

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