BAR CODES
A bar code, Fig. B/1, is a rectangular block of black and white lines often seen printed on cans of food, books and many other items. It is a method of coding consumer products by combinations of bars of varying thicknesses representing characters and numerals. The black lines and white spaces tell a computer what the item is and how much the item costs. The various codes, Universal Product Code (UPC), and others are designed to be read by optical wands or stationary in-counter readers.
Fig. B/1 Bar code.
A great deal of work could be avoided if it were possible to input information by speech rather than by digital recording ...
Get Consumer Electronics now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
