A Universal Product Code is found in barcode form on virtually everything tangible we purchase today, from food items to clothes to even furniture and household items. While they look like black-and-white lines and jumbles of numbers to the untrained eye, they're actually specific color-coded tracking devices that anyone can learn to read, not just machines.
The standard UPC barcodes have twelve decimal places, with ten digits below the black-and-white lines, as well as one smaller number on either side of the ten digits, making twelve in all. There are four different thicknesses of lines, numbered one through four. Most barcodes in the US and Canada begin with 101 for general products, with varying degrees of beginning numbers to represent different products, such as pharmacy drugs that begin with the number three.
The smallest, skinniest black line is numbered one; the next-thickest one is two; the one a size after that is numbered three; and the thickest black line is numbered four. Every decimal below the lines on a UPC barcode has four lines in a set that represent it; therefore, since there are only four digits, every line set adds up to seven, because each four-line code is seven lines wide. If a product's UPC label starts with 101, followed by a 06, that 06 itself has eight color bars to represent the numbers. Broken down by thickness of the lines, which are always the same for numbers one through four, the 06 will read "10132111114". 101 is the beginning of the code, followed by "3211" representing zero, and "1114" representing six. All of those numbers together represent eight lines on the barcode, making up just two little numerals on the UPC itself.
Every barcode is broken into two halves - one smaller number and five smaller numbers separated by two thin black lines in the middle. The numbers on the first half of the barcode represent the company that manufactures the product; after the dividing lines, the color scheme of the barcode goes from black-white-black to white-black-white, which tells the machine reading the barcode which way is the right way to be scanned. All UPC barcodes start with a black line to delineate the right way to be scanned.
Good eyesight and a memory of what the lines represent, as well as a little bit of practice, will help you to read and understand UPC barcodes in no time.