Computers

Computers - what makes them click?

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bar code

Printed series of parallel bars of varying width used for entering data into a computer system, typically for identifying the object on which the code appears. The width and spacing of the bars represent binary information that can be read by an optical (laser) scanner that is part of a computer system. The coding is used in many different areas of manufacturing and marketing, including inventory control and tracking systems. The bar codes printed on supermarket and other retail merchandise are those of the Universal Product Code (UPC).

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