Bar codes

What's a barcode?

A  barcode is a symbol used to represent a numerical or alphabetical code. One uses barcodes instead of characters in order to automate the process of acquisition of the data for electronic material, almost a computer. A barcode scanner is abble to 'read' a printed barcode quickly, it decodes the symbol, checks the validity of the resulting code to eliminate eventual reading errors, then the code is send to the computer. The continuing expansion of bar codes in the modern world is proof of the power of the solution.

What's for?

Firstly you need a barcode if you want to easely mark a physical good for further quick acquisition, by you or by others. This highlights one of the avantages of barcodes, their universality. Or simply you have to generate a barcode if you have something to sell in retail shops.

What's in?

A  barcode is a simple graph, generally made up of large and thin vertical bars with large and thin spaces between. Each character composing the code is translated in a serie of spaces and bars. Other information is added to the graph, to simplify the reading of the barcode, or for identify the barcode's type, including mostly one or more checksum characters, and often an alphabetical representation, usefull for the Human reader.

What are the different barcode types?

(*) A for alphanumeric, N for Numeric-only
Type
A/N (*)
# of chars
Primary use
UPC
N
12 (11+1) Identification of retail goods in USA and Canada
EAN 13
N
13 (12+1) Identification of retail goods worldwide (except USA/Canada)
JAN
N
13 (12+1) Idem EAN13 for Japan
SCC 14
N
14 (13+1) Shipping cartons containing UPC or EAN identified products
ISBN-EAN
N
13 (21+1) Identification of books and videos in ISBN, encoded in a EAN barcode type

There's a lot of other barcodes types, you could learn more on Barcode-1