Chapter 7

Input is a data and instructions entered into the memory of a computer. There are many items that commonly used input methods include keyboard, touch screens, pen input and many more. As we know, most desktop keyboards have typing area, function keys, toggle keys, directional keys, media control buttons and internet control buttons. A pointer is a small symbol on the screen whose location and shape change as a user moves a pointing device such as mouse. A touch screen is a touch-sensitive display device. Other than that, we also can use pen input, graphic tablet, motion input, voice input, audio input and video input. A scanner is a light-sensing input device that reads printed text and graphics and then translates the results into a form the computer can process while an optical reader is a device that uses a light source to read characters,  marks, and codes and then converts them into digital data that a computer can process. A bar code reader, also called a bar code scanner uses laser beams to read bar codes. A QR code stores information in both a vertical and horizontal direction. Magstripe readers and MICR also can be categorized as a reading devices. Proceeding to the topic output, Output is data that has been processed into a useful form. Output is data that has been processed into a useful form. The medium that shows output is such as monitor, HDTV, printer, speakers, headphones and so on. The quality of a display depends primarily on its resolution, response time, brightness, dot pitch and also contrast ratio.