Input and Output devices

By Azam Khan 8-C

Any machine that feeds data into a computer is called an input device. For example, a keyboard is an input device, whereas a display monitor is an output device. Input devices other than the keyboard are sometimes called alternate input devices. Mouse, trackballs, and light pens are all alternate input devices.

INPUT DEVICES

GRAPHIC TABLETA graphics tablet or digitizer is a

computer input device that enables a user to hand-draw images and graphics, similar to the way a person draws images with a pencil and paper. These tablets may also be used to capture data or handwritten signatures. It can also be used to trace an image from a piece of paper which is taped or otherwise secured to the surface.

The device consists of a flat surface upon which the user may "draw" or trace an image using an attached stylus, a pen-like drawing apparatus. The image generally does not appear on the tablet itself but, rather, is displayed on the computer monitor.

MICRMagnetic ink character recognition, or MICR, is a

character recognition technology used primarily by the banking industry to facilitate the processing and clearance of cheques and other documents. The MICR encoding, called the MICR line, is located at the bottom of a cheque or other voucher and typically includes the document type indicator, bank code , bank account number, cheque number and the amount, plus some control indicator. The technology allows MICR readers to scan and read the information directly into a data collection device. Unlike barcodes or similar technologies, MICR characters can be easily read by humans.

OCROptical character recognition, usually

abbreviated to OCR, is the mechanical or electronic conversion of scanned images of handwritten, typewritten or printed text into machine-encoded text. It is widely used as a form of data entry from some sort of original paper data source, whether documents, sales receipts, mail, or any number of printed records. It is a common method of digitizing printed texts so that they can be electronically searched, stored more compactly, displayed on-line, and used in machine processes such as machine translation, text-to-speech and text mining .

OMROMR,Short

for optical mark recognition, the technology of electronically extracting intended data from marked fields, such as checkboxes and fill-infields, on printed forms. OMR technology scans a printed form and reads predefined positions and records where marks are made on the form. This technology is useful for applications in which large numbers of hand-filled forms need to be processed quickly and with great accuracy, such as surveys, reply cards, questionnaires and ballots. A common OMR application is the use of "bubble sheets" for multiple-choice tests used by schools. 

Magnetic Stripsa strip of magnetic material on w

hich information may be stored, as by an electromagnetic process, for automatic reading, decoding, or recognition by a device that detects magnetic variations on the strip: accredit card with a magnetic strip to prevent counterfeiting.

Smart CardA smart card, or integrated circuit

card (ICC) is any pocket-sized card with embedded integrated circuits. Smart cards are made of plastic, generally polyvinyl chloride, but sometimes  polycarbonate.

Smart cards serve as credit or ATM cards, fuel cards, mobile phone SIMs, authorization cards for pay television, household utility pre-payment cards, high-security identification and access-control cards, and public transport and public phone payment cards.

Touch ScreenA touch screen is an electronic

visual display that the user can control through simple or multi-touch gestures by touching the screen with one or more fingers. Some touch screens can also detect objects such as a stylus or ordinary or specially coated gloves. The user can use the touch screen to react to what is displayed and to control how it is displayed .

MICROPHONE

A microphone is a transducer or sensor that converts sound into an electrical signal. Microphones are used in many applications such as telephones, tape recorders, karaoke systems, hearing aids, motion picture production, live and recorded audio engineering, FRS radios, megaphones, in radio and television broadcasting and in computers for recording voice, speech recognition, VoIP.

Output devicesThe devices which are used to

display the data to the user either in the form of hard copy or soft copy are called output devices.

The monitor is the most common output device.

Braille EmbosserA Braille embosser is an impact

printer that renders text as tactile Braille cells. Using Braille translation software, a document can be embossed with relative ease, making Braille production efficient and cost-effective.

 an embosser can cost roughly anywhere from US$2,000 to $150,000.

PlotterA plotter is a printer that interprets

commands from a computer to make line drawings on paper with one or more automated pens. Unlike a regular printer , the plotter can draw continuous point-to-point lines directly from vector graphics files or commands. There are a number of different types of plotters.

Drum PlotterA type of pen plotter that

wraps the paper around a drum with a pin feed attachment. The drum turns to produce one direction of the plot, and the pens move to provide the other. The plotter was the first output device to print graphics and large engineering drawings. Using different colored pens, it could draw in color long before color inkjet printers became viable. 

Flatbed PlotterFlatbed plotter: A graphic plotter

that contains a flat surface that the paper is placed on. The size of this surface (bed) determines the maximum size of the drawing. 

Micrographic PlotterMicrographic plotters do not use

drums the paper or any other medium is held on both sides at the edges by pinch wheels which give back and forth movement of the paper

Inkjet PlotterThe inkjet plotter uses jets of ink pens.

The paper is placed on a drum and inkjets with different colored inks are mounted on a carriage. These are capable of producing multicolored, large drawings.