Completar frases 282-testVersión en línea 282-test por Farhad Key 1 intensity many sequentially principle seeing that translates reflect manipulate Many different types of bar code scanning machines exist , but they all work on the same fundamental principles . They all use the of light reflected from a series of black and white stripes to tell a computer what code it is . White stripes light very well , while black stripes reflect hardly any light at all . The bar code scanner shines light across a bar code , simultaneously detecting and recording the pattern of reflected and non - reflected light . The scanner then this pattern into an electrical signal the computer can understand . All scanners must include computer software to interpret the bar code once it's been entered . This simple has transformed the way we are able to data and the way in which businesses handle recordkeeping .