What Are Those Funny Little Square Things I Now See Everywhere?

EVERYWHERE YOU GO YOU CAN HARDLY PICK UP AN ADVERTISEMENT, PRODUCT BROCHURE, LOOK AT A BILLBOARD, SURF THE INTERNET OR JUST WALK DOWN THE AVENUE WITHOUT SEEING MANY OF THESE LITTLE SQUARE THINGS IN MORE AND MORE PLACES EACH AND EVERY DAY.

WHAT ARE THEY? ACTUALLY THESE MYSTERIOUS SQUARES ARE CALLED TWO DIMENSIONAL BAR CODES. THIS BOOK WILL PROVIDE THE READER WITH SOME INTERESTING AND ENTERTAINING ...