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On the back of credit/debit cards, there is a thin black stripe (known as a magnetic stripe). Such stripes contain
              coded information in the form of magnetic marks and are read when the card is inserted into the ATM.



                                         Light Pen

                                         Light Pen is a pen-like device which uses a light-sensitive detector to select or
                                         draw objects on the display screen.




              It is similar to a mouse, except that with a light pen one can move the pointer on the screen by touching it
              on the objects on the screen. When the pen is moved across the screen, its position is sensed because of the
              light it emits.



                     Do you know?

                     A Tablet PC is slate shaped notebook computer. Its technology allows the user to operate the computer
                     with stylus, digital pen or fingertip, instead of using a keyboard or mouse.


              Barcode Reader

              Barcode  Reader  is a  popular  scanning  device that  reads  the  bar  codes.  Bar  codes
              comprise adjacent vertical black bars of different widths.

              Bars are codes that represent different numbers. One can see the bar code on the back
              cover of this book as well. A bar code reader emits a beam of light (laser beam), which
              re ects the bar code image. A light-sensitive detector is present in the bar code reader
              which identifies and reads the bar code image. The bar pattern is changed into numeric
              code inside the CPU.






                           Microphone

                           Microphone  is a voice-based input device.  With the help of this device,  sound or  voice is
                           recognized/recorded in the computer and is converted into digital form which is then played or
                           processed by the computer.




              Digital Camera
              Digital Camera  captures the image or  picture momentarily  and  converts
              the image directly into digital form and stores it in memory. It can then be
              viewed on the computer or compatible devices.

              It is available in various models with different specifications that include pixels,
              sizes and memory. The quality of the image captured by a digital camera                              i s
              measured in pixels.


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